ジョージア・イタリア医学部で使う

ジョージア・イタリア医学部で使う

英語医学単語

Medical English Vocabulary 1000
for Medical Students in Georgia and Italy
Volume 1 — Anatomy
第1巻　解剖学（100語）
Kosuke Onishi, Esq.
大西好祐（おおにし こうすけ）

© Kosuke Onishi / Onishi Press
All rights reserved. No part of this book may be reproduced without permission.
本書の無断複製・転載を禁じます。
知識は贅沢品ではなく、権利である。 —— Knowledge is not a luxury; it is a right.
はじめに / Preface
海外の医学部で学ぶ日本人学生にとって、最初の壁は「医学そのもの」よりも「医学を語る英語」であることが少なくありません。授業も、教科書も、試験も、そして患者との会話も、すべて英語で進みます。日本語ではすでに知っている概念でさえ、英語の専門用語に置き換わった瞬間、急に遠い存在になってしまうのです。
本シリーズは、ジョージアやイタリアをはじめとする海外医学部で実際に必要となる医学英単語を、分野ごとに整理し、一語ずつ丁寧に身につけられるよう構成しました。第1巻のテーマは、すべての医学の土台となる「解剖学（Anatomy）」です。骨・筋・血管・神経・臓器——人体を構成する基本的な構造を表す100語を厳選しています。
各単語は1ページに1語ずつ、英語の定義、例文、その日本語訳、そして臨床や学習に役立つ「Medical Tip」をそえて掲載しました。ただ暗記するのではなく、「その言葉が実際の医療現場でどう使われるのか」を感じながら学べることを目指しています。

For students studying medicine abroad, the first barrier is often not medicine itself, but the English used to talk about it. Lectures, textbooks, examinations, and conversations with patients all unfold in English. Even a concept you already understand in your own language can suddenly feel distant once it is dressed in unfamiliar technical terms.
This series gathers the medical English vocabulary that students actually need at medical schools in Georgia, Italy, and beyond, organized by subject so that each word can be learned carefully, one at a time. The theme of Volume 1 is anatomy, the foundation of all medicine: one hundred essential words for the bones, muscles, vessels, nerves, and organs that make up the human body.
Each word is presented on its own page, with an English definition, an example sentence, a Japanese translation, and a short "Medical Tip" drawn from clinical practice or study. The aim is not rote memorization, but learning each word together with a sense of how it is truly used at the bedside.
本書の使い方 / How to Use This Book
Headword（見出し語）
見出し語（英単語） / The English term to learn.
ページの上部に大きく示された医学英単語です。
Meaning（意味）
A plain-English definition of the term.
その単語のやさしい英語による定義です。英語のまま意味をつかむ練習になります。
Example（例文）
A natural example sentence used in clinical context.
臨床の場面を想定した自然な英語の例文です。
日本語（Japanese）
A Japanese translation of the example sentence.
例文の日本語訳です。文の構造ごと理解の助けになります。
Medical Tip
A short clinical or study note about the term.
その単語にまつわる臨床的・学習上のひとことメモです。

学習のヒント：1日10語を目安に、まず英語の意味と例文を声に出して読み、次に日本語訳で確認してください。1巻100語を10日で一周し、それを3周すると定着します。
シリーズ構成 / The Series
本シリーズは、医学英単語1000語を分野別に5巻へ分けて学ぶ構成です。
Vol. 1 Anatomy 解剖学 — 本巻 / This volume
Vol. 2 Physiology 生理学
Vol. 3 Pathology 病理学
Vol. 4 Pharmacology 薬理学
Vol. 5 Psychiatry 精神医学
No. 1 / 100 · Anatomy
Skull

Meaning: The bony framework of the head that encloses and protects the brain.
Example: A CT scan revealed a hairline fracture of the skull after the fall.
日本語：転倒後のCT検査で、頭蓋骨に細い亀裂骨折が認められた。
Medical Tip: The skull is made up of 22 bones, only one of which—the mandible—is freely movable.
No. 2 / 100 · Anatomy
Cranium

Meaning: The portion of the skull that surrounds and protects the brain.
Example: The neurosurgeon opened the cranium to relieve the rising intracranial pressure.
日本語：脳神経外科医は、上昇した頭蓋内圧を下げるために頭蓋を開いた。
Medical Tip: Clinically, "cranium" usually refers to the braincase, while "skull" includes the facial bones as well.
No. 3 / 100 · Anatomy
Mandible

Meaning: The lower jawbone, the only freely moving bone of the skull.
Example: The dislocated mandible was gently reduced under local anesthesia.
日本語：脱臼した下顎骨は、局所麻酔下で慎重に整復された。
Medical Tip: It is the strongest bone of the face and a common site of fracture in trauma.
No. 4 / 100 · Anatomy
Clavicle

Meaning: The collarbone, connecting the sternum to the shoulder blade.
Example: He landed on his outstretched arm and fractured his clavicle.
日本語：彼は腕を伸ばしたまま着地し、鎖骨を骨折した。
Medical Tip: The clavicle is the most frequently fractured bone in the body, especially in cyclists and children.
No. 5 / 100 · Anatomy
Scapula

Meaning: The shoulder blade, a flat triangular bone of the upper back.
Example: Winging of the scapula suggested injury to the long thoracic nerve.
日本語：肩甲骨の翼状突出は、長胸神経の損傷を示唆していた。
Medical Tip: Scapular winging is a classic sign of serratus anterior weakness.
No. 6 / 100 · Anatomy
Sternum

Meaning: The breastbone, a flat bone in the center of the chest.
Example: Chest compressions are delivered to the lower half of the sternum.
日本語：胸骨圧迫は、胸骨の下半分に対して行われる。
Medical Tip: The sternal angle (angle of Louis) is a key landmark at the level of the second rib.
No. 7 / 100 · Anatomy
Rib

Meaning: One of the twelve pairs of curved bones forming the chest wall.
Example: A fractured rib can puncture the lung and cause a pneumothorax.
日本語：肋骨が骨折すると肺を傷つけ、気胸を起こすことがある。
Medical Tip: Humans have 12 pairs of ribs; the lower two pairs are called "floating ribs."
No. 8 / 100 · Anatomy
Vertebra

Meaning: One of the small bones forming the spinal column.
Example: The compressed vertebra was the source of her chronic back pain.
日本語：圧迫された椎骨が、彼女の慢性的な腰痛の原因だった。
Medical Tip: The vertebral column has 33 vertebrae, grouped into cervical, thoracic, lumbar, sacral, and coccygeal regions.
No. 9 / 100 · Anatomy
Pelvis

Meaning: The basin-shaped ring of bone connecting the spine to the legs.
Example: A pelvis fracture from the crash caused significant internal bleeding.
日本語：事故による骨盤骨折は、大量の内出血を引き起こした。
Medical Tip: The female pelvis is generally wider and shallower to accommodate childbirth.
No. 10 / 100 · Anatomy
Femur

Meaning: The thigh bone, the longest and strongest bone in the body.
Example: An elderly woman was admitted with a fractured neck of femur.
日本語：高齢の女性が大腿骨頸部骨折で入院した。
Medical Tip: Hip fracture in the elderly almost always refers to a fracture of the femoral neck.
No. 11 / 100 · Anatomy
Tibia

Meaning: The shinbone, the larger of the two bones of the lower leg.
Example: The open tibia fracture required urgent surgical fixation.
日本語：開放性の脛骨骨折には、緊急の手術固定が必要だった。
Medical Tip: The tibia bears most of the body's weight; the fibula bears very little.
No. 12 / 100 · Anatomy
Fibula

Meaning: The slender bone running alongside the tibia in the lower leg.
Example: Surgeons harvested a section of fibula to reconstruct the jaw.
日本語：外科医は、顎を再建するために腓骨の一部を採取した。
Medical Tip: Because it bears little weight, a fibular segment is often used as a bone graft.
No. 13 / 100 · Anatomy
Humerus

Meaning: The single bone of the upper arm.
Example: A fracture of the humerus can injure the nearby radial nerve.
日本語：上腕骨の骨折は、近くを走る橈骨神経を傷つけることがある。
Medical Tip: Mid-shaft humeral fractures are classically associated with wrist drop from radial nerve damage.
No. 14 / 100 · Anatomy
Radius

Meaning: The bone on the thumb side of the forearm.
Example: She fell on her hand and sustained a distal radius fracture.
日本語：彼女は手をついて転び、橈骨遠位端骨折を起こした。
Medical Tip: A distal radius fracture (Colles fracture) is one of the most common fractures in older adults.
No. 15 / 100 · Anatomy
Ulna

Meaning: The bone on the little-finger side of the forearm.
Example: The point of the elbow is formed by the upper end of the ulna.
日本語：肘の先端は、尺骨の上端によって形づくられている。
Medical Tip: The olecranon process of the ulna gives the elbow its bony point.
No. 16 / 100 · Anatomy
Patella

Meaning: The kneecap, a small bone covering the front of the knee joint.
Example: He dislocated his patella while pivoting during the game.
日本語：彼は試合中に方向転換した際、膝蓋骨を脱臼した。
Medical Tip: The patella is the largest sesamoid bone, embedded within the quadriceps tendon.
No. 17 / 100 · Anatomy
Cartilage

Meaning: Firm, flexible connective tissue that cushions joints and shapes structures.
Example: Worn cartilage in the knee is a hallmark of osteoarthritis.
日本語：膝の軟骨のすり減りは、変形性関節症の特徴である。
Medical Tip: Cartilage has no direct blood supply, which is why it heals very slowly.
No. 18 / 100 · Anatomy
Ligament

Meaning: A band of fibrous tissue that connects one bone to another.
Example: The athlete tore the anterior cruciate ligament of his knee.
日本語：その選手は膝の前十字靱帯を断裂した。
Medical Tip: Remember: ligaments connect bone to bone, while tendons connect muscle to bone.
No. 19 / 100 · Anatomy
Tendon

Meaning: A tough cord of fibrous tissue attaching muscle to bone.
Example: A ruptured Achilles tendon left him unable to push off his foot.
日本語：アキレス腱の断裂により、彼は足で地面を蹴ることができなくなった。
Medical Tip: The Achilles tendon is the thickest and strongest tendon in the human body.
No. 20 / 100 · Anatomy
Joint

Meaning: The place where two or more bones meet and allow movement.
Example: Swelling of the joint pointed toward an inflammatory arthritis.
日本語：関節の腫れは、炎症性の関節炎を示唆していた。
Medical Tip: Synovial joints, such as the knee and shoulder, are the most movable type of joint.
No. 21 / 100 · Anatomy
Muscle

Meaning: Tissue that contracts to produce movement or maintain posture.
Example: Prolonged bed rest leads to rapid loss of muscle mass.
日本語：長期間の安静臥床は、急速な筋肉量の減少を招く。
Medical Tip: There are three types of muscle: skeletal, cardiac, and smooth.
No. 22 / 100 · Anatomy
Skeleton

Meaning: The internal framework of bones that supports the body.
Example: The adult human skeleton contains 206 bones.
日本語：成人の人体の骨格は206個の骨から構成されている。
Medical Tip: Newborns are born with about 270 bones; many fuse together as they grow.
No. 23 / 100 · Anatomy
Heart

Meaning: The muscular organ that pumps blood throughout the body.
Example: The patient's heart was beating irregularly on the monitor.
日本語：モニター上で、患者の心臓は不規則に拍動していた。
Medical Tip: The heart beats roughly 100,000 times a day, about 3 billion times in an average lifetime.
No. 24 / 100 · Anatomy
Atrium

Meaning: One of the two upper chambers of the heart that receive blood.
Example: Blood from the body returns to the right atrium.
日本語：全身から戻った血液は、右心房に流れ込む。
Medical Tip: Atrial fibrillation, a quivering of the atria, is the most common sustained arrhythmia.
No. 25 / 100 · Anatomy
Ventricle

Meaning: One of the two lower, pumping chambers of the heart.
Example: The left ventricle pumps oxygenated blood into the aorta.
日本語：左心室は、酸素を含んだ血液を大動脈へ送り出す。
Medical Tip: The left ventricle has a thicker wall than the right because it pumps against higher pressure.
No. 26 / 100 · Anatomy
Artery

Meaning: A blood vessel that carries blood away from the heart.
Example: A blocked coronary artery can trigger a heart attack.
日本語：冠動脈が詰まると、心筋梗塞を引き起こすことがある。
Medical Tip: Most arteries carry oxygen-rich blood, but the pulmonary artery is an exception.
No. 27 / 100 · Anatomy
Vein

Meaning: A blood vessel that carries blood back toward the heart.
Example: A clot in a deep vein of the leg may travel to the lungs.
日本語：脚の深部静脈にできた血栓は、肺へと移動することがある。
Medical Tip: Veins contain one-way valves that keep blood flowing toward the heart against gravity.
No. 28 / 100 · Anatomy
Capillary

Meaning: The smallest blood vessel, where exchange of gases and nutrients occurs.
Example: Oxygen diffuses from the capillary into the surrounding tissue.
日本語：酸素は毛細血管から周囲の組織へと拡散していく。
Medical Tip: Capillary walls are only one cell thick, allowing rapid diffusion of substances.
No. 29 / 100 · Anatomy
Aorta

Meaning: The largest artery in the body, leaving the left ventricle.
Example: A widening of the aorta raised concern for an aneurysm.
日本語：大動脈の拡張は、動脈瘤の可能性を疑わせた。
Medical Tip: A ruptured aortic aneurysm is a surgical emergency with a very high mortality rate.
No. 30 / 100 · Anatomy
Vena cava

Meaning: Either of two large veins returning blood to the right atrium.
Example: The superior vena cava drains blood from the head and arms.
日本語：上大静脈は、頭部と腕からの血液を集めて心臓へ戻す。
Medical Tip: The body has a superior vena cava (upper body) and an inferior vena cava (lower body).
No. 31 / 100 · Anatomy
Valve

Meaning: A flap-like structure that keeps blood flowing in one direction.
Example: A narrowed aortic valve forces the heart to work harder.
日本語：狭窄した大動脈弁は、心臓により大きな負担を強いる。
Medical Tip: The four heart valves are the tricuspid, pulmonary, mitral, and aortic valves.
No. 32 / 100 · Anatomy
Pericardium

Meaning: The double-layered membranous sac surrounding the heart.
Example: Fluid collecting in the pericardium can compress the heart.
日本語：心膜腔にたまった液体は、心臓を圧迫することがある。
Medical Tip: A large pericardial effusion can cause cardiac tamponade, a life-threatening emergency.
No. 33 / 100 · Anatomy
Myocardium

Meaning: The thick, muscular middle layer of the heart wall.
Example: A heart attack causes part of the myocardium to die.
日本語：心筋梗塞では、心筋の一部が壊死してしまう。
Medical Tip: "Myocardial infarction" literally means death of heart muscle tissue.
No. 34 / 100 · Anatomy
Lung

Meaning: One of the two spongy organs of respiration in the chest.
Example: Years of smoking had badly damaged the patient's lungs.
日本語：長年の喫煙が、患者の肺をひどく傷つけていた。
Medical Tip: The right lung has three lobes, while the left has only two to make room for the heart.
No. 35 / 100 · Anatomy
Trachea

Meaning: The windpipe, carrying air between the larynx and the bronchi.
Example: A breathing tube was passed through the mouth into the trachea.
日本語：気管チューブが口から気管へと挿入された。
Medical Tip: The trachea is held open by C-shaped rings of cartilage.
No. 36 / 100 · Anatomy
Bronchus

Meaning: One of the two main airways branching from the trachea into the lungs.
Example: The inhaled peanut lodged in the right main bronchus.
日本語：吸い込んだピーナッツは、右主気管支に詰まった。
Medical Tip: Foreign bodies more often enter the right bronchus because it is wider and more vertical.
No. 37 / 100 · Anatomy
Alveolus

Meaning: A tiny air sac in the lung where gas exchange takes place.
Example: In pneumonia, fluid fills the alveoli and impairs breathing.
日本語：肺炎では、肺胞が液体で満たされ、呼吸が障害される。
Medical Tip: The lungs contain roughly 300 million alveoli, giving an enormous surface area for gas exchange.
No. 38 / 100 · Anatomy
Diaphragm

Meaning: The dome-shaped muscle that drives breathing, below the lungs.
Example: The diaphragm contracts and flattens to draw air into the lungs.
日本語：横隔膜が収縮して平らになることで、空気が肺に取り込まれる。
Medical Tip: The diaphragm is the primary muscle of inspiration, controlled by the phrenic nerve.
No. 39 / 100 · Anatomy
Pleura

Meaning: The thin membrane covering the lungs and lining the chest cavity.
Example: Inflammation of the pleura causes sharp pain on breathing.
日本語：胸膜の炎症は、呼吸時に鋭い痛みを引き起こす。
Medical Tip: The space between the two pleural layers is normally only a thin film of lubricating fluid.
No. 40 / 100 · Anatomy
Larynx

Meaning: The voice box, containing the vocal cords.
Example: Swelling of the larynx can rapidly block the airway.
日本語：喉頭の腫れは、急速に気道を閉塞させることがある。
Medical Tip: The larynx houses the vocal cords and produces sound as air passes through them.
No. 41 / 100 · Anatomy
Pharynx

Meaning: The throat, a passage shared by the respiratory and digestive tracts.
Example: A streptococcal infection of the pharynx caused a severe sore throat.
日本語：咽頭の連鎖球菌感染が、ひどい喉の痛みを引き起こした。
Medical Tip: The pharynx is divided into the nasopharynx, oropharynx, and laryngopharynx.
No. 42 / 100 · Anatomy
Esophagus

Meaning: The muscular tube carrying food from the throat to the stomach.
Example: Acid reflux gradually inflamed the lining of the esophagus.
日本語：胃酸の逆流が、食道の粘膜を徐々に炎症させた。
Medical Tip: Food moves down the esophagus by waves of muscle contraction called peristalsis.
No. 43 / 100 · Anatomy
Stomach

Meaning: The hollow organ that mixes food with acid and enzymes.
Example: The endoscope showed an ulcer in the lining of the stomach.
日本語：内視鏡では、胃の粘膜に潰瘍が認められた。
Medical Tip: Stomach acid is so strong (about pH 1.5–2) that it can dissolve metal.
No. 44 / 100 · Anatomy
Liver

Meaning: The large organ that processes nutrients, detoxifies, and makes bile.
Example: Chronic alcohol use can scar the liver, leading to cirrhosis.
日本語：慢性的な飲酒は肝臓に瘢痕を残し、肝硬変へとつながる。
Medical Tip: The liver is the only internal organ capable of regenerating significant lost tissue.
No. 45 / 100 · Anatomy
Gallbladder

Meaning: The small sac beneath the liver that stores and concentrates bile.
Example: The inflamed gallbladder was removed laparoscopically.
日本語：炎症を起こした胆嚢は、腹腔鏡下で摘出された。
Medical Tip: Gallstones blocking the duct are the most common reason for gallbladder removal.
No. 46 / 100 · Anatomy
Pancreas

Meaning: The gland producing digestive enzymes and the hormone insulin.
Example: Inflammation of the pancreas caused severe upper abdominal pain.
日本語：膵臓の炎症が、激しい上腹部の痛みを引き起こした。
Medical Tip: The pancreas has both an exocrine role (enzymes) and an endocrine role (insulin and glucagon).
No. 47 / 100 · Anatomy
Spleen

Meaning: The organ that filters blood and supports the immune system.
Example: A ruptured spleen after the accident required emergency surgery.
日本語：事故後の脾臓破裂には、緊急手術が必要だった。
Medical Tip: The spleen sits in the upper left abdomen and is easily injured in blunt trauma.
No. 48 / 100 · Anatomy
Duodenum

Meaning: The first, C-shaped section of the small intestine.
Example: Most peptic ulcers actually occur in the duodenum.
日本語：消化性潰瘍の多くは、実は十二指腸に生じる。
Medical Tip: The duodenum receives bile and pancreatic juice to continue digestion.
No. 49 / 100 · Anatomy
Jejunum

Meaning: The middle section of the small intestine, where most absorption occurs.
Example: Nutrients are mainly absorbed across the wall of the jejunum.
日本語：栄養素は主に空腸の壁を通して吸収される。
Medical Tip: The small intestine's inner folds and villi vastly increase its absorptive surface area.
No. 50 / 100 · Anatomy
Ileum

Meaning: The final section of the small intestine, joining the large bowel.
Example: Vitamin B12 is absorbed in the terminal ileum.
日本語：ビタミンB12は、回腸末端で吸収される。
Medical Tip: Crohn's disease commonly affects the terminal ileum.
No. 51 / 100 · Anatomy
Colon

Meaning: The large intestine, which absorbs water and forms stool.
Example: A routine colonoscopy found a polyp in the colon.
日本語：定期的な大腸内視鏡検査で、結腸にポリープが見つかった。
Medical Tip: The colon is divided into ascending, transverse, descending, and sigmoid portions.
No. 52 / 100 · Anatomy
Rectum

Meaning: The final straight segment of the large intestine before the anus.
Example: Bright red blood from the rectum prompted further investigation.
日本語：直腸からの鮮紅色の出血が、さらなる精査のきっかけとなった。
Medical Tip: A digital rectal examination is a simple but important part of many clinical assessments.
No. 53 / 100 · Anatomy
Appendix

Meaning: A small finger-like pouch projecting from the large intestine.
Example: An inflamed appendix must usually be removed surgically.
日本語：炎症を起こした虫垂は、通常は手術で摘出する必要がある。
Medical Tip: Appendicitis classically begins as central abdominal pain that shifts to the right lower quadrant.
No. 54 / 100 · Anatomy
Intestine

Meaning: The long tube of the digestive tract beyond the stomach.
Example: A blockage of the intestine caused vomiting and distension.
日本語：腸の閉塞が、嘔吐と腹部膨満を引き起こした。
Medical Tip: The small intestine handles most digestion and absorption; the large intestine reclaims water.
No. 55 / 100 · Anatomy
Kidney

Meaning: One of two organs that filter blood and produce urine.
Example: Poorly controlled diabetes slowly damaged both kidneys.
日本語：コントロール不良の糖尿病が、両方の腎臓を徐々に傷つけた。
Medical Tip: The kidneys filter about 180 liters of blood every day, yet produce only 1–2 liters of urine.
No. 56 / 100 · Anatomy
Ureter

Meaning: The tube carrying urine from the kidney to the bladder.
Example: A kidney stone lodged in the ureter caused excruciating pain.
日本語：尿管に詰まった腎結石が、激烈な痛みを引き起こした。
Medical Tip: Ureteric colic is often described as one of the most severe pains a person can experience.
No. 57 / 100 · Anatomy
Bladder

Meaning: The muscular sac that stores urine until it is passed.
Example: The patient could not empty the bladder after surgery.
日本語：患者は手術後、膀胱を空にすることができなかった。
Medical Tip: The adult bladder typically holds about 400–600 milliliters of urine.
No. 58 / 100 · Anatomy
Urethra

Meaning: The tube that carries urine from the bladder out of the body.
Example: An enlarged prostate can squeeze and narrow the urethra.
日本語：肥大した前立腺は、尿道を圧迫して狭くすることがある。
Medical Tip: The female urethra is much shorter than the male, which is why urinary infections are more common in women.
No. 59 / 100 · Anatomy
Nephron

Meaning: The microscopic filtering unit of the kidney.
Example: Each kidney contains about one million nephrons.
日本語：それぞれの腎臓には、およそ100万個のネフロンが存在する。
Medical Tip: The nephron is where filtration, reabsorption, and secretion all take place.
No. 60 / 100 · Anatomy
Brain

Meaning: The central organ of the nervous system, housed in the skull.
Example: An MRI of the brain was ordered to investigate the headaches.
日本語：頭痛の原因を調べるため、脳のMRIが指示された。
Medical Tip: The brain uses about 20% of the body's oxygen and energy despite being only 2% of its weight.
No. 61 / 100 · Anatomy
Cerebrum

Meaning: The largest part of the brain, controlling thought and movement.
Example: A stroke in the cerebrum left her with weakness on one side.
日本語：大脳の脳卒中により、彼女は片側に麻痺が残った。
Medical Tip: The cerebrum is divided into two hemispheres, each controlling the opposite side of the body.
No. 62 / 100 · Anatomy
Cerebellum

Meaning: The part of the brain that coordinates balance and movement.
Example: Damage to the cerebellum produced an unsteady, staggering gait.
日本語：小脳の損傷により、不安定でふらつく歩行が生じた。
Medical Tip: The cerebellum fine-tunes movement; its damage causes ataxia, not paralysis.
No. 63 / 100 · Anatomy
Brainstem

Meaning: The stalk-like base of the brain controlling vital functions.
Example: The brainstem regulates breathing, heart rate, and consciousness.
日本語：脳幹は、呼吸・心拍・意識を調節している。
Medical Tip: Because it controls vital functions, brainstem injury is often fatal.
No. 64 / 100 · Anatomy
Spinal cord

Meaning: The bundle of nerves running within the spinal column.
Example: The fall injured the spinal cord and caused leg paralysis.
日本語：転落により脊髄が損傷し、両脚の麻痺が生じた。
Medical Tip: The spinal cord ends around the first lumbar vertebra in most adults.
No. 65 / 100 · Anatomy
Nerve

Meaning: A bundle of fibers that carries signals between body and brain.
Example: Pressure on the nerve produced tingling down the arm.
日本語：神経への圧迫が、腕に走るしびれを引き起こした。
Medical Tip: Nerves can be sensory, motor, or mixed depending on the signals they carry.
No. 66 / 100 · Anatomy
Neuron

Meaning: A nerve cell that transmits electrical and chemical signals.
Example: In Parkinson's disease, dopamine-producing neurons gradually die.
日本語：パーキンソン病では、ドーパミンを産生する神経細胞が徐々に死んでいく。
Medical Tip: The human brain contains an estimated 86 billion neurons.
No. 67 / 100 · Anatomy
Synapse

Meaning: The junction where one neuron communicates with another.
Example: Many drugs act on receptors at the synapse.
日本語：多くの薬は、シナプスにある受容体に作用する。
Medical Tip: Signals cross the synapse using chemical messengers called neurotransmitters.
No. 68 / 100 · Anatomy
Meninges

Meaning: The three protective membranes covering the brain and spinal cord.
Example: Infection of the meninges is known as meningitis.
日本語：髄膜の感染症は、髄膜炎と呼ばれる。
Medical Tip: The three layers are the dura mater, arachnoid mater, and pia mater.
No. 69 / 100 · Anatomy
Medulla

Meaning: The lowest part of the brainstem, controlling breathing and heart rate.
Example: The medulla houses the centers that keep us breathing.
日本語：延髄には、私たちの呼吸を維持する中枢が存在する。
Medical Tip: The medulla oblongata controls automatic functions we never consciously think about.
No. 70 / 100 · Anatomy
Thyroid

Meaning: A butterfly-shaped gland in the neck regulating metabolism.
Example: An underactive thyroid left the patient tired and cold.
日本語：甲状腺の機能低下により、患者は倦怠感と冷えを訴えた。
Medical Tip: The thyroid sits over the trachea and produces hormones that set the body's metabolic rate.
No. 71 / 100 · Anatomy
Adrenal gland

Meaning: A small gland atop each kidney producing stress hormones.
Example: The adrenal glands release cortisol and adrenaline under stress.
日本語：副腎は、ストレス下でコルチゾールとアドレナリンを分泌する。
Medical Tip: The adrenal medulla makes adrenaline, while the cortex makes steroid hormones like cortisol.
No. 72 / 100 · Anatomy
Pituitary gland

Meaning: The pea-sized "master gland" at the base of the brain.
Example: A tumor of the pituitary gland disturbed her hormone balance.
日本語：下垂体の腫瘍が、彼女のホルモンバランスを乱した。
Medical Tip: The pituitary controls many other glands, earning it the name "master gland."
No. 73 / 100 · Anatomy
Hypothalamus

Meaning: The brain region that links the nervous and hormonal systems.
Example: The hypothalamus regulates temperature, hunger, and thirst.
日本語：視床下部は、体温・空腹・喉の渇きを調節している。
Medical Tip: The hypothalamus is the body's main control center for homeostasis.
No. 74 / 100 · Anatomy
Uterus

Meaning: The womb, the muscular organ where a fetus develops.
Example: The fertilized egg implants in the lining of the uterus.
日本語：受精卵は、子宮の内膜に着床する。
Medical Tip: The inner lining of the uterus, the endometrium, is shed each month during menstruation.
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Ovary

Meaning: One of two female glands that produce eggs and hormones.
Example: A cyst on the ovary was found during the ultrasound.
日本語：超音波検査の際、卵巣に嚢胞が見つかった。
Medical Tip: The ovaries release one egg per cycle and produce estrogen and progesterone.
No. 76 / 100 · Anatomy
Testis

Meaning: One of two male glands that produce sperm and testosterone.
Example: Sudden pain in the testis may signal a surgical emergency.
日本語：精巣の突然の痛みは、外科的緊急事態を示すことがある。
Medical Tip: Testicular torsion is a true emergency requiring surgery within hours to save the testis.
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Prostate

Meaning: A gland surrounding the male urethra below the bladder.
Example: The prostate commonly enlarges with age, causing urinary symptoms.
日本語：前立腺は加齢とともに肥大し、排尿障害を引き起こすことが多い。
Medical Tip: The prostate gland adds fluid to semen and tends to enlarge in older men.
No. 78 / 100 · Anatomy
Eye

Meaning: The organ of vision that detects light and forms images.
Example: A foreign body in the eye was carefully irrigated out.
日本語：目に入った異物は、慎重に洗浄して取り除かれた。
Medical Tip: The eye works much like a camera, focusing light onto a light-sensitive layer.
No. 79 / 100 · Anatomy
Cornea

Meaning: The clear, dome-shaped front surface of the eye.
Example: A scratch on the cornea caused intense pain and watering.
日本語：角膜の擦り傷が、激しい痛みと涙を引き起こした。
Medical Tip: The cornea does most of the eye's focusing and contains no blood vessels.
No. 80 / 100 · Anatomy
Retina

Meaning: The light-sensitive layer at the back of the eye.
Example: A detached retina is a medical emergency threatening vision.
日本語：網膜剥離は、視力を脅かす医学的緊急事態である。
Medical Tip: The retina converts light into nerve signals sent to the brain via the optic nerve.
No. 81 / 100 · Anatomy
Ear

Meaning: The organ responsible for hearing and balance.
Example: An infection of the middle ear is common in young children.
日本語：中耳の感染症は、幼い子どもによく見られる。
Medical Tip: The ear has three parts: the outer, middle, and inner ear.
No. 82 / 100 · Anatomy
Cochlea

Meaning: The spiral, fluid-filled structure of the inner ear for hearing.
Example: A cochlear implant can restore hearing in profound deafness.
日本語：人工内耳は、高度難聴において聴覚を回復させることができる。
Medical Tip: The cochlea converts sound vibrations into nerve signals the brain can interpret.
No. 83 / 100 · Anatomy
Tongue

Meaning: The muscular organ used for taste, speech, and swallowing.
Example: The doctor asked the patient to stick out the tongue.
日本語：医師は患者に、舌を突き出すように指示した。
Medical Tip: The tongue is one of the strongest muscles relative to its size in the body.
No. 84 / 100 · Anatomy
Tooth

Meaning: One of the hard structures in the mouth used for chewing.
Example: A decayed tooth can lead to a painful abscess.
日本語：虫歯は、痛みを伴う膿瘍につながることがある。
Medical Tip: Tooth enamel is the hardest substance in the human body.
No. 85 / 100 · Anatomy
Skin

Meaning: The body's outer protective covering and largest organ.
Example: A persistent change in a mole on the skin should be checked.
日本語：皮膚のほくろに持続的な変化があれば、診てもらうべきである。
Medical Tip: The skin is the body's largest organ and its first barrier against infection.
No. 86 / 100 · Anatomy
Epidermis

Meaning: The thin, outermost layer of the skin.
Example: A superficial burn injures only the epidermis.
日本語：表在性の熱傷では、表皮のみが損傷する。
Medical Tip: The epidermis has no blood vessels and constantly renews itself from below.
No. 87 / 100 · Anatomy
Dermis

Meaning: The thick inner layer of skin containing nerves and vessels.
Example: Deep cuts reach the dermis and tend to scar.
日本語：深い切り傷は真皮に達し、瘢痕を残しやすい。
Medical Tip: The dermis houses hair follicles, sweat glands, blood vessels, and nerve endings.
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Bone

Meaning: The rigid, living tissue forming the skeleton.
Example: Weak, thinning bone increases the risk of fracture.
日本語：もろく薄くなった骨は、骨折のリスクを高める。
Medical Tip: Bone is living tissue that constantly remodels itself throughout life.
No. 89 / 100 · Anatomy
Blood

Meaning: The fluid that transports oxygen, nutrients, and waste.
Example: A sample of blood was drawn to check the cell counts.
日本語：血球数を確認するため、血液の検体が採取された。
Medical Tip: Blood makes up about 7–8% of total body weight in a healthy adult.
No. 90 / 100 · Anatomy
Lymph node

Meaning: A small bean-shaped organ that filters lymph and fights infection.
Example: Swollen lymph nodes in the neck suggested an infection.
日本語：頸部のリンパ節の腫れは、感染症を示唆していた。
Medical Tip: Lymph nodes trap bacteria and cancer cells, which is why they are checked during exams.
No. 91 / 100 · Anatomy
Lymphatic vessel

Meaning: A thin channel that carries lymph through the body.
Example: Cancer can spread through the lymphatic vessels to distant sites.
日本語：がんはリンパ管を通じて、離れた部位に広がることがある。
Medical Tip: The lymphatic system returns excess tissue fluid back to the bloodstream.
No. 92 / 100 · Anatomy
Membrane

Meaning: A thin layer of tissue that lines or covers body structures.
Example: The mucous membrane of the nose became inflamed and swollen.
日本語：鼻の粘膜が炎症を起こし、腫れあがった。
Medical Tip: Membranes can be epithelial (like mucous membranes) or connective tissue layers.
No. 93 / 100 · Anatomy
Organ

Meaning: A self-contained structure performing a specific bodily function.
Example: The liver is the largest internal organ in the body.
日本語：肝臓は、体内で最も大きな臓器である。
Medical Tip: Organs working together toward a common purpose form an organ system.
No. 94 / 100 · Anatomy
Tissue

Meaning: A group of similar cells working together for a function.
Example: A small piece of tissue was taken for biopsy.
日本語：生検のために、ごく小さな組織片が採取された。
Medical Tip: The four basic tissue types are epithelial, connective, muscle, and nervous tissue.
No. 95 / 100 · Anatomy
Cell

Meaning: The basic structural and functional unit of life.
Example: Cancer arises when a single cell begins dividing uncontrollably.
日本語：がんは、一つの細胞が制御を失って分裂し始めることで生じる。
Medical Tip: The adult human body is made up of roughly 37 trillion cells.
No. 96 / 100 · Anatomy
Gland

Meaning: An organ that produces and releases substances such as hormones.
Example: A salivary gland became blocked by a small stone.
日本語：唾液腺が、小さな結石によって閉塞した。
Medical Tip: Glands are either exocrine (releasing through ducts) or endocrine (releasing into the blood).
No. 97 / 100 · Anatomy
Cavity

Meaning: A hollow space within the body that contains organs.
Example: The abdominal cavity holds the stomach, liver, and intestines.
日本語：腹腔には、胃・肝臓・腸が収まっている。
Medical Tip: The body's two largest cavities are the thoracic (chest) and abdominal cavities.
No. 98 / 100 · Anatomy
Abdomen

Meaning: The region of the body between the chest and the pelvis.
Example: The patient complained of cramping pain in the lower abdomen.
日本語：患者は、下腹部のけいれん性の痛みを訴えた。
Medical Tip: Clinicians divide the abdomen into four quadrants or nine regions to localize pain.
No. 99 / 100 · Anatomy
Thorax

Meaning: The chest region, between the neck and the diaphragm.
Example: A chest X-ray revealed fluid within the thorax.
日本語：胸部X線では、胸腔内に液体の貯留が認められた。
Medical Tip: The thorax is protected by the rib cage and contains the heart and lungs.
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Fascia

Meaning: The sheet of connective tissue surrounding muscles and organs.
Example: A severe infection spread rapidly along the fascia.
日本語：重篤な感染が、筋膜に沿って急速に広がった。
Medical Tip: Necrotizing fasciitis, a "flesh-eating" infection, spreads along the fascial planes.