WordNet (r) 3.0 (2006):

formalistic
    adj 1: concerned with or characterized by rigorous adherence to
           recognized forms (especially in religion or art); "highly
           formalized plays like `Waiting for Godot'" [syn:
           formalistic, formalized, formalised]

Moby Thesaurus II by Grady Ward, 1.0:

52 Moby Thesaurus words for "formalistic":
   accordant, anal, bourgeois, compulsive, concordant, conformist,
   conventional, conventionalized, corresponding, elegant,
   euphemistic, euphuistic, exquisite, extrinsic, formal, formalist,
   formulary, goody good-good, goody-goody, harmonious, impersonal,
   in accord, in keeping, in line, in step, kosher, legalistic,
   mincing, namby-pamby, nominal, orthodox, outward, overnice,
   overprecise, overrefined, pedantic, plastic, precieuse, precious,
   precisian, precisianistic, precisionistic, puristic, simpering,
   square, straight, stuffy, stylized, superficial, surface,
   traditionalist, uptight