Source : Webster's Revised Unabridged Dictionary (1913)

Wary \Wa"ry\, a. [Compar. {Warier}; superl. {Wariest}.] [OE.
   war, AS. w[ae]r; akin to Icel. v?rr, Dan. & Sw. var, Goth.
   wars, G. gewahr aware, OHG. wara notice, attention, Gr. ? to
   see. Cf. {Aware}, {Garment}, {Garnish}, {Garrison},
   {Panorama}, {Ward}, v. t. {Ware}, a., {Warren}.]
   1. Cautious of danger; carefully watching and guarding
      against deception, artifices, and dangers; timorously or
      suspiciously prudent; circumspect; scrupulous; careful.
      ``Bear a wary eye.'' --Shak.

            We should be wary, therefore, what persecution we
            raise against the living labors of public men.
                                                  --Milton.

   2. Characterized by caution; guarded; careful.

            It behoveth our words to be wary and few. --Hooker.

   Syn: Cautious; circumspect; watchful. See {Cautious}.

Source : WordNet®

wary
     adj 1: marked by keen caution and watchful prudence; "they were
            wary in their movements"; "a wary glance at the black
            clouds"; "taught to be wary of strangers" [ant: {unwary}]
     2: openly distrustful and unwilling to confide [syn: {leery}, {mistrustful},
         {suspicious}, {untrusting}]
     [also: {wariest}, {warier}]