o·nan·ism
noun/ˈəʊnənɪzəm/
/ˈəʊnənɪzəm/
[uncountable] (formal)- masturbation the act of giving yourself or another person sexual pleasure by rubbing the sexual organs
手淫：手淫通过摩擦性器官使自己或他人获得性快感的行为 - an act of sexual intercourse in which the man removes his penis from the woman’s body before he ejaculates, in order to prevent the woman from becoming pregnant
（为防止受孕而在射精前抽出阴茎的）不完全性交
Word Originearly 18th cent.: from French onanisme or modern Latin onanismus, from the biblical name Onan (Genesis 38:9), who practised coitus interruptus.