What does "fluent" mean?

Fluent: Ready in the use of words; voluble; copious; having words at command; and uttering them with facility and smoothness; as, a fluent speaker; hence, flowing; voluble; smooth; -- said of language; as, fluent speech. With most fluent utterance. Denham. Fluent as the flight of a swallow is the sultan's letter. De Quincey.

Additional senses

  1. 2.A current of water; a stream. [Obs.]
  2. 3.Etym: [Cf. F. fluente.] (Math.) A variable quantity, considered as increasing or diminishing; - - called, in the modern calculus, the function or integral.

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