- fluent (adj.)
[fluent 词源字典] - 1580s, "flowing freely" (of water), also, of speakers, "able and nimble in the use of words," from Latin fluentem (nominative fluens) "lax, relaxed," figuratively "flowing, fluent," present participle of fluere "to flow, stream, run, melt," from extended form of PIE root *bhleu- "to swell, well up, overflow" (cognates: Latin flumen "river;" Greek phluein "to boil over, bubble up," phlein "to abound"), an extension of root *bhel- (2) "to blow, inflate, swell;" see bole. Used interchangeably with fluid (adj.) in 17c. in the sense "changeable, not rigid." Related: Fluently.
[fluent etymology, fluent origin, 英语词源]
