The Collaborative International Dictionary of English v.0.48:

Vaporization \Vap`o*ri*za"tion\
   (v[a^]p`[-o]*r[imac]*z[.a]"sh[u^]n or
   v[=a]`p[~e]r*[imac]*z[.a]"sh[u^]n), n. [Cf. F. vaporisation.]
   The act or process of vaporizing, or the state of being
   converted into vapor; the artificial formation of vapor;
   specifically, the conversion of water into steam, as in a
   steam boiler.
   [1913 Webster]
   [1913 Webster]

WordNet (r) 3.0 (2006):

vaporization
    n 1: annihilation by vaporizing something [syn: vaporization,
         vaporisation]
    2: the process of becoming a vapor [syn: vaporization,
       vaporisation, vapor, vapour, evaporation]