also: はにく
noun
Anatomical term for the gums; used in medical and everyday contexts.
歯肉が腫れて痛いです。
My gums are swollen and painful.
歯肉炎は歯肉の炎症です。
Gingivitis is inflammation of the gums.
歯茎 is the more common, everyday word for gums; 歯肉 is a formal anatomical term.
Compound of 歯 (tooth) and 肉 (flesh). The reading しにく uses the on'yomi of both kanji, while はにく mixes kun'yomi and on'yomi.