The Collaborative International Dictionary of English v.0.48:

Conversant \Con"ver*sant\, a. [L. conversans, p. pr. of
   conversari: cf. F. conversant.]
   1. Having frequent or customary intercourse; familiary
      associated; intimately acquainted.
      [1913 Webster]

            I have been conversant with the first persons of the
            age.                                  --Dryden.
      [1913 Webster]

   2. Familiar or acquainted by use or study; well-informed;
      versed; -- generally used with with, sometimes with in.
      [1913 Webster]

            Deeply conversant in the Platonic philosophy.
                                                  --Dryden.
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            he uses the different dialects as one who had been
            conversant with them all.             --Pope.
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            Conversant only with the ways of men. --Cowper.
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   3. Concerned; occupied.
      [1913 Webster]

            Education . . . is conversant about children. --W.
                                                  Wotton.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Conversant \Con*vers"ant\, n.
   One who converses with another; a convenser. [R.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

conversant
    adj 1: (usually followed by `with') well informed about or
           knowing thoroughly; "conversant with business trends";
           "familiar with the complex machinery"; "he was familiar
           with those roads" [syn: conversant(p), familiar(p)]

Moby Thesaurus II by Grady Ward, 1.0:

50 Moby Thesaurus words for "conversant":
   abreast, accomplished, acquainted, acquainted with, alive,
   apprehending, apprehensive, at concert pitch, at home in,
   at home with, au courant, au fait, awake, career, coached,
   cognizant, comprehending, conscious, conversant with,
   familiar with, finished, informed, informed in, initiate,
   initiated, intimate with, knowing, master of, no stranger to,
   perceptive, percipient, practiced, prepared, primed, professional,
   proficient in, sensible, sentient, skilled, strong in, technical,
   trained, up, up on, up-to-date, used to, versed, versed in,
   well-read in, witting



Bouvier's Law Dictionary, Revised 6th Ed (1856):

CONVERSANT. One who is in the habit of being in a particular place, is said
to be conversant there. Barnes, 162.