The Collaborative International Dictionary of English v.0.48:

Multipartite \Mul*tip"ar*tite\, a. [L. multipartitus multus
   much, many partitus divided, p. p.: cf. F. multipartite. See
   Partite.]
   Divided into many parts; having several parts.
   [1913 Webster]

WordNet (r) 3.0 (2006):

multipartite
    adj 1: involving more than two parties