The kanji 胆 primarily represents "gallbladder," but it also carries the broader meanings of "courage," "nerve," "guts," or "spirit." It signifies something inside that is essential for life, both physically (the gallbladder) and metaphorically (courage).

・On-yomi (音読み): タン ・Kun-yomi (訓読み): きも

⚫︎ 肝胆相照らす Translation: To be open-hearted with each other; to confide in each other (literally: to show one's liver and gallbladder to each other). ⚫︎ 胆力 Translation: Courage; nerve; guts; spirit. ⚫︎ 小心 Translation: Timidity; cowardice (literally: small gallbladder).

The kanji 胆 is a phono-semantic compound (形声文字). The left side, 月 (also written as 肉), is the radical for "flesh" or "body." This indicates that 胆 relates to something inside the body. The right side, 旦, is the phonetic component, originally representing "dawn" or "daybreak," lending the sound タン. The combination of the two suggests an organ inside the body that is essential for daily life, referring to the gallbladder. Over time, the meaning expanded to include courage, representing the "inner strength" or "spirit."