Source : Webster's Revised Unabridged Dictionary (1913)

Legalization \Le`gal*i*za"tion\ (l[=e]`gal*[i^]*z[=a]"sh[u^]n),
   n.
   The act of making legal.

Source : WordNet®

legalization
     n : the act of making lawful [syn: {legalisation}, {legitimation}]