preform

from WordNet (r) 3.0 (2006)

preform
    v 1: form into a shape resembling the final, desired one
    2: form or shape beforehand or determine the shape of beforehand

from The Collaborative International Dictionary of English v.0.48

Preform \Pre*form"\, v. t. [L. praeformare. See {Pre-}, and
   {Form}.]
   To form beforehand, or for special ends. "Their natures and
   preformed faculties. " --Shak.
   [1913 Webster]