The Collaborative International Dictionary of English v.0.48:

Conventionalization \Con*ven`tion*al*i*za"tion\, n. (Fine Arts)
   (a) The act of making conventional.
   (b) The state of being conventional.
       [1913 Webster]

WordNet (r) 3.0 (2006):

conventionalization
    n 1: the act of conventionalizing; conforming to a conventional
         style [syn: conventionalization, conventionalisation]