The Collaborative International Dictionary of English v.0.48:

Efflux \Ef*flux"\, v. i.
   To run out; to flow forth; to pass away. [Obs.] --Boyle.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Efflux \Ef"flux\, n. [See Effluent, Flux.]
   1. The act or process of flowing out, or issuing forth;
      effusion; outflow; as, the efflux of matter from an ulcer;
      the efflux of men's piety.
      [1913 Webster]

            It is then that the devout affections . . . are
            incessantly in efflux.                --I. Taylor.
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   2. That which flows out; emanation; effluence.
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            Prime cheerer, light! . . .
            Efflux divine.                        --Thomson.
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WordNet (r) 3.0 (2006):

efflux
    n 1: the process of flowing out [syn: outflow, effluence,
         efflux] [ant: inflow, influx]