Source : Webster's Revised Unabridged Dictionary (1913)

Exert \Ex*ert"\, v. t. [imp. & p. p. {Exerted}; p. pr. & vb. n.
   {Exerting}.] [L. exertus, exsertus, p. p. of exerere,
   exserere, to thrust out; ex out + serere to join or bind
   together. See {Series}, and cf. {Exsert}.]
   1. To thrust forth; to emit; to push out. [Obs.]

            So from the seas exerts his radiant head The star by
            whom the lights of heaven are led.    --Dryden.

   2. To put force, ability, or anything of the nature of an
      active faculty; to put in vigorous action; to bring into
      active operation; as, to exert the strength of the body,
      limbs, faculties, or imagination; to exert the mind or the
      voice.

   3. To put forth, as the result or exercise of effort; to
      bring to bear; to do or perform.

            When we will has exerted an act of command on any
            faculty of the soul or member of the body. --South.

   {To exert one's self}, to use efforts or endeavors; to
      strive; to make an attempt.