The Collaborative International Dictionary of English v.0.48:

Pierid \Pi"er*id\, n. [See Peirides.] (Zool.)
   Any butterfly of the genus Pieris and related genera. See
   Cabbage butterfly, under Cabbage.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pierid
    n 1: any of numerous pale-colored butterflies having three pairs
         of well-developed legs [syn: pierid, pierid butterfly]