The Collaborative International Dictionary of English v.0.48:
Multilateral \Mul`ti*lat"er*al\, a. [Multi- + lateral.] Having many sides; many-sided. [1913 Webster]WordNet (r) 3.0 (2006):
multilateral adj 1: having many parts or sides [syn: multilateral, many- sided] [ant: one-sided, unilateral]