The Collaborative International Dictionary of English v.0.48:

manila bean \manila bean\ n.
   A tuberous-rooted twining annual vine (Psophocarpus
   tetragonolobus) bearing clusters of purplish flowers and
   pods with four jagged wings; Old World tropics.

   Syn: winged bean, winged pea, goa bean, goa bean vine,
        Psophocarpus tetragonolobus.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Psophocarpus tetragonolobus
    n 1: a tuberous twining annual vine bearing clusters of purplish
         flowers and pods with four jagged wings; Old World tropics
         [syn: winged bean, winged pea, goa bean, goa bean
         vine, Manila bean, Psophocarpus tetragonolobus]