反曲
retroflection n 1: a turning or tilting backward of an organ or body part; "retroversion of the uterus" [syn: {retroversion}, {retroflexion}] 2: an articulatory gesture made by turning the tip of the tongue back against the roof of the mouth [syn: {retroflexion}] 3: the act of bending backward [syn: {retroflexion}]