c. 1600, "that which flows out;" 1620s, "act of flowing out," from Late Latin effluentia, from Latin effluentem (nominative effluens) "flowing out," present participle of effluere "to flow out," from ex- "out" (see ex-) + fluere "to flow" (see fluent). Related: Effluency.[effluence etymology, effluence origin, 英语词源]