gallbladder; liver
Anatomical term for the gallbladder; also used in traditional contexts to refer to the liver or the concept of 'innards'. In modern medical Japanese, 胆嚢 (たんのう) is more common for gallbladder, and 肝臓 (かんぞう) for liver. This reading い is rare and mostly found in classical or compound words.
The character 胆 used to refer to the liver or gallbladder in the past.
courage-testing event; test of courage
The kanji 胆 originally referred to the gallbladder, but historically it was also used for the liver or internal organs in general. The reading い is a native Japanese reading (kun'yomi) that is now rare.