flaccid (adj.)youdaoicibaDictYouDict[flaccid 词源字典]
1610s, from French flaccide or directly from Latin flaccidus "flabby, pendulous, weak, drooping," from flaccus "flabby, flap-eared," which is of uncertain origin (OED suggests it's imitative). Related: Flaccidly; flacidness; flaccidity; flaccescency.[flaccid etymology, flaccid origin, 英语词源]