Source : Webster's Revised Unabridged Dictionary (1913)

Avail \A*vail"\, v. t. [imp. & p. p. {Availed} (?); p. pr. & vb.
   n. {Availing}.] [OE. availen, fr. F. ? (L. ad) + valoir to be
   worth, fr. L. valere to be strong, to be worth. See
   {Valiant}.]
   1. To turn to the advantage of; to be of service to; to
      profit; to benefit; to help; as, artifices will not avail
      the sinner in the day of judgment.

            O, what avails me now that honor high ! --Milton.

   2. To promote; to assist. [Obs.] --Pope.

   {To avail one's self of}, to make use of; take advantage of.

            Then shall they seek to avail themselves of names.
                                                  --Milton.

            I have availed myself of the very first opportunity.
                                                  --Dickens.

Avail \A*vail"\, v. i.
   To be of use or advantage; to answer the purpose; to have
   strength, force, or efficacy sufficient to accomplish the
   object; as, the plea in bar must avail, that is, be
   sufficient to defeat the suit; this scheme will not avail;
   medicines will not avail to check the disease. ``What signs
   avail ?'' --Milton.

         Words avail very little with me, young man. --Sir W.
                                                  Scott.

Avail \A*vail"\, n.
   1. Profit; advantage toward success; benefit; value; as,
      labor, without economy, is of little avail.

            The avail of a deathbed repentance.   --Jer. Taylor.

   2. pl. Proceeds; as, the avails of a sale by auction.

            The avails of their own industry.     --Stoddard.

   Syn: Use; benefit; utility; profit; service.

Avail \A*vail"\, v. t. & i.
   See {Avale}, v. [Obs.] --Spenser.

Source : WordNet®

avail
     n : a means of serving; "of no avail"; "there's no help for it"
         [syn: {help}, {service}]
     v 1: use to one's advantage; "He availed himself of the available
          resources"
     2: be of use to, be useful to; "It will avail them to dispose
        of their booty"
     3: take or use; "She helped herself to some of the office
        supplies" [syn: {help}]