penetration (n.)youdaoicibaDictYouDict[penetration 词源字典]
c. 1600, "insight, shrewdness," from Latin penetrationem (nominative penetratio) "a penetrating or piercing," noun of action from past participle stem of penetrare (see penetrate). The sexual sense is attested from 1610s.[penetration etymology, penetration origin, 英语词源]