Source : Webster's Revised Unabridged Dictionary (1913)

Evaporate \E*vap"o*rate\, v. t.
   1. To convert from a liquid or solid state into vapor
      (usually) by the agency of heat; to dissipate in vapor or
      fumes.

   2. To expel moisture from (usually by means of artificial
      heat), leaving the solid portion; to subject to
      evaporation; as, to evaporate apples.

   3. To give vent to; to dissipate. [R.]

            My lord of Essex evaporated his thoughts in a
            sonnet.                               --Sir. H.
                                                  Wotton.

   {Evaporating surface} (Steam Boilers), that part of the
      heating surface with which water is in contact.