Source : Webster's Revised Unabridged Dictionary (1913)

Thirst \Thirst\, n. [OE. thirst, [thorn]urst, AS. [thorn]urst,
   [thorn]yrst; akin to D. dorst, OS. thurst, G. durst, Icel.
   [thorn]orsti, Sw. & Dan. t["o]rst, Goth. [thorn]a['u]rstei
   thirst, [thorn]a['u]rsus dry, withered,
   [thorn]a['u]rsie[thorn] mik I thirst, ga[thorn]a['i]rsan to
   wither, L. torrere to parch, Gr. te`rsesqai to become dry,
   tesai`nein to dry up, Skr. t[.r]sh to thirst. [root]54. Cf.
   {Torrid}.]
   1. A sensation of dryness in the throat associated with a
      craving for liquids, produced by deprivation of drink, or
      by some other cause (as fear, excitement, etc.) which
      arrests the secretion of the pharyngeal mucous membrane;
      hence, the condition producing this sensation.

            Wherefore is this that thou hast brought us up out
            of Egypt, to kill us, and our children . . . with
            thirst?                               --Ex. xvii. 3.

            With thirst, with cold, with hunger so confounded.
                                                  --Chaucer.

   2. Fig.: A want and eager desire after anything; a craving or
      longing; -- usually with for, of, or after; as, the thirst
      for gold. ``Thirst of worldy good.'' --Fairfax. ``The
      thirst I had of knowledge.'' --Milton.

Thirst \Thirst\, v. t. [imp. & p. p. {Thirsted}; p. pr. & vb. n.
   {Thirsting}.] [AS. [thorn]yrstan. See {Thirst}, n.]
   1. To feel thirst; to experience a painful or uneasy
      sensation of the throat or fauces, as for want of drink.

            The people thirsted there for water.  --Ex. xvii. 3.

   2. To have a vehement desire.

            My soul thirsteth for . . . the living God. --Ps.
                                                  xlii. 2.

Thirst \Thirst\, v. t.
   To have a thirst for. [R.]

         He seeks his keeper's flesh, and thirsts his blood.
                                                  --Prior.

Source : WordNet®

thirst
     n 1: a physiological need to drink
     2: strong desire for something (not food or drink); "a thirst
        for knowledge"; "hunger for affection" [syn: {hunger}]
     v 1: feel the need to drink
     2: have a craving, appetite, or great desire for [syn: {crave},
         {hunger}, {starve}, {lust}]