腺
xiàn · HSK 7
gland
月 flesh + 泉 spring = a fluid-spring inside the body, i.e. a gland
The 月 radical marks body/flesh words; 泉 means spring or fountain. A gland is the organ that wells up fluid, so flesh + spring spells it out. 泉 quán also nudges the xiàn sound.
腺 — flesh radical 月 (肉) + spring 泉
A relatively modern semantic-phonetic compound. The 月 (flesh/body) radical signals a bodily organ, while 泉 (spring, source of water) provides the sound and hints at fluid secretion. Together they denote a 'gland' — a body part that secretes fluid, a meaning coined in the modern era for anatomy.