Source : Webster's Revised Unabridged Dictionary (1913)

Prevent \Pre*vent"\, v. i.
   To come before the usual time. [Obs.]

         Strawberries . . . will prevent and come early.
                                                  --Bacon.

Prevent \Pre*vent"\, v. t. [imp. & p. p. {Prevented}; p. pr. &
   vb. n. {Preventing}.] [L. praevenire, praeventum; prae before
   + venire to come. See {Come}.]
   1. To go before; to precede; hence, to go before as a guide;
      to direct. [Obs.]

            We which are alive and remain unto the coming of the
            Lord shall not prevent them which are asleep. --1
                                                  Thess. iv. 15.

            We pray thee that thy grace may always prevent and
            follow us.                            --Bk. of
                                                  Common Prayer.

            Then had I come, preventing Sheba's queen. --Prior.

   2. To be beforehand with; to anticipate. [Obs.]

            Their ready guilt preventing thy commands. --Pope.

   3. To intercept; to hinder; to frustrate; to stop; to thwart.
      ``This vile purpose to prevent.'' --Shak.

            Perhaps forestalling night prevented them. --Milton.

Source : WordNet®

prevent
     v 1: keep from happening or arising; have the effect of
          preventing; "My sense of tact forbids an honest answer"
          [syn: {forestall}, {foreclose}, {preclude}, {forbid}]
     2: prevent from doing something or being in a certain state;
        "We must prevent the cancer from spreading"; "His snoring
        kept me from falling asleep"; "Keep the child from eating
        the marbles" [syn: {keep}] [ant: {let}]