Source : Webster's Revised Unabridged Dictionary (1913)

Exigent \Ex"i*gent\, n.
   1. Exigency; pressing necessity; decisive moment. [Obs.]

            Why do you cross me in this exigent?  --Shak.

   2. (o. Eng. Law) The name of a writ in proceedings before
      outlawry. --Abbott.

Exigent \Ex`i*gent\, a. [L. exigens, -entis, p. pr. of exigere
   to drive out or forth, require, exact. See {Exact}.]
   Exacting or requiring immediate aid or action; pressing;
   critical. ``At this exigent moment.'' --Burke.

Source : WordNet®

exigent
     adj 1: demanding attention; "clamant needs"; "a crying need";
            "regarded literary questions as exigent and
            momentous"- H.L.Mencken; "insistent hunger"; "an
            instant need" [syn: {clamant}, {crying}, {insistent},
            {instant}]
     2: requiring precise accuracy; "an exacting job"; "became more
        exigent over his pronunciation" [syn: {exacting}]