Meaning
The kanji 胆 carries two meanings that, at first glance, seem unrelated: the physical gallbladder — the organ that stores and concentrates bile — and, by metaphorical extension, courage, boldness, and guts. The connection comes from ancient East Asian medicine, where the gallbladder was considered the seat of willpower and decisiveness. A person with a strong gallbladder was brave and clear-headed; a weak one made someone timid and hesitant. That belief ran through Chinese, Japanese, Korean, and Vietnamese traditions for over two thousand years, and its traces survive in modern Japanese idioms.
Structurally, 胆 is built from two components. On the left sits ⺼, the "flesh" or "meat" radical — a variant of 月 (moon) that marks any kanji relating to the body or its organs. The same radical appears in 肝 (liver), 肺 (lungs), 腸 (intestines), and 脳 (brain). On the right is 旦, meaning "dawn" or "daybreak" — the sun (日) rising above the horizon (一). Inside 胆, the component 旦 serves as a phonetic indicator, giving the character its on'yomi reading of タン (tan). The two parts together signal: a body part pronounced like 旦 — the gallbladder.
In everyday Japanese, 胆 rarely stands alone. It works inside compound words (熟語), carrying either its anatomical meaning — 胆嚢 (gallbladder) or 胆汁 (bile) — or its figurative sense of inner strength, as in 大胆 (bold, daring) and 落胆 (discouragement). Knowing both sides of 胆 opens up vocabulary that spans medical textbooks and literary prose alike.
胆 takes 9 strokes and belongs to the grade 8 category of the Jōyō kanji list — secondary school level. Essential for JLPT N1, it comes up regularly in medical texts, literature, and classical Japanese prose.
Readings
On'yomi (音読み) — Chinese-derived readings
胆 has one primary on'yomi: タン (tan). Borrowed from Middle Chinese, it appears almost exclusively in compounds and formal vocabulary — medical terms, four-character idioms (四字熟語), and literary expressions about strength of character.
- 大胆 (daitan) — boldness, audacity, daring
- 大胆不敵 (daitan futeki) — completely fearless, undaunted (four-character idiom)
- 胆力 (tanryoku) — courage, nerve, strength of will
- 落胆 (rakutan) — discouragement, despondency, loss of heart
- 胆汁 (tanjuu) — bile (the digestive fluid produced by the liver)
- 胆石 (tanseki) — gallstone
- 胆嚢 (tannou) — gallbladder (the organ)
- 胆管 (tankan) — bile duct
When you spot 胆 in a two-character compound, it is nearly always read as タン. The image inside 落胆 — the gallbladder literally dropping — makes the ancient belief tangible: discouragement physically deflates the organ of courage.
Kun'yomi (訓読み) — Native Japanese readings
胆 has one kun'yomi: きも (kimo). This native Japanese word once referred broadly to the liver or internal organs and came to mean guts, pluck, and deep inner courage. It lives in colloquial speech rather than formal writing. The closely related kanji 肝 (liver) shares the kimo reading. The two occasionally appear interchangeably in set phrases — a remnant of how folk medicine once grouped these organs together.
- 胆 (kimo) — guts, courage, liver (informal, poetic)
- 胆が太い (kimo ga futoi) — to be bold, to have thick nerves (lit. "one's guts are thick")
- 肝っ玉 (kimottama) — guts, nerve, pluck (lively colloquial expression)
肝っ玉が据わっている (kimottama ga suwatte iru — "one's guts are settled") is a vivid way to describe someone utterly unflappable. Use きも in conversation; save タン for formal writing and medical vocabulary.
Common Words & Compounds
The following compounds feature 胆, grouped by theme.
Courage, Character & Spirit
- 大胆 (daitan) — bold, daring, audacious
- 大胆不敵 (daitan futeki) — utterly fearless, intrepid (four-character idiom)
- 胆力 (tanryoku) — courage, strength of nerve, fortitude
- 胆が太い (kimo ga futoi) — bold, having thick nerves, unshakeable
- 肝っ玉 (kimottama) — guts, nerve, pluck
Emotions & Morale
- 落胆 (rakutan) — discouragement, disappointment, low spirits
- 肝胆 (kantan) — one's innermost heart and soul, deepest feelings
- 肝胆相照らす (kantan ai terasu) — to be true kindred spirits, to have deep mutual understanding (classical idiom)
Medical & Anatomical
- 胆嚢 (tannou) — gallbladder
- 胆汁 (tanjuu) — bile
- 胆石 (tanseki) — gallstone
- 胆管 (tankan) — bile duct
- 胆道 (tandou) — biliary tract
- 胆嚢炎 (tannouen) — cholecystitis, gallbladder inflammation
Example Sentences
彼は大胆な計画を提案した。
Kare wa daitan na keikaku wo teian shita.
He proposed a bold plan.
試合に負けて、チーム全員が落胆した。
Shiai ni makete, chiimu zen'in ga rakutan shita.
After losing the match, the entire team was discouraged.
あの警官は胆力があって、どんな危険にも動じない。
Ano keikan wa tanryoku ga atte, donna kiken ni mo ugojinai.
That police officer has great nerve and doesn't flinch in the face of any danger.
医者は胆石を取り除く手術を行った。
Isha wa tanseki wo torinozoku shujutsu wo okonatta.
The doctor performed surgery to remove the gallstone.
あの子は肝っ玉が据わっていて、何があっても平気な顔をしている。
Ano ko wa kimottama ga suwatte ite, nani ga atte mo heiki na kao wo shite iru.
That child has real guts and keeps a calm face no matter what happens.
大胆不敵な態度で敵に立ち向かった。
Daitan futeki na taido de teki ni tachi mukatta.
He confronted the enemy with a completely fearless attitude.
胆嚢炎は早めに治療しないと危険です。
Tannouen wa hayame ni chiryou shinai to kiken desu.
Gallbladder inflammation is dangerous if not treated early.
二人は肝胆相照らす友だちで、何でも話し合える。
Futari wa kantan ai terasu tomodachi de, nan demo hanashi aeru.
The two are true kindred spirits who can talk openly about anything.
彼女の大胆な発言は会議の雰囲気を一変させた。
Kanojo no daitan na hatsugen wa kaigi no fun'iki wo ippen saseta.
Her bold statement completely changed the atmosphere of the meeting.
胆汁は脂肪の消化を助ける重要な役割を果たしている。
Tanjuu wa shibou no shouka wo tasukeru juuyou na yakuwari wo hatashite iru.
Bile plays an important role in helping the body digest fats.
Memory Tip
The left side of 胆 (tan / kimo) is the flesh radical ⺼ — it marks this as a body part. The right side is 旦 (sun rising above the horizon), which supplies the タン reading. Picture a warrior at first light, steadying his gut before battle: 胆 is the organ where resolve lives. The compounds follow naturally. 大胆 (daitan) — big guts, bold. 落胆 (rakutan) — guts that have dropped, a spirit deflated. When your 胆 rises, you are fearless; when it falls, you lose heart.