The Collaborative International Dictionary of English v.0.48:

Plicate \Pli"cate\, Plicated \Pli"ca*ted\, a. [L. plicatus, p.
   p. of plicare to fold.]
   Plaited; folded like a fan; as, a plicate leaf. --
   Pli"cate*ly, adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

plicate
    v 1: fold into pleats, "Pleat the cloth" [syn: pleat,
         plicate]