Source : WordNet®

Liliopsida
     n : comprising seed plants that produce an embryo with a single
         cotyledon and parallel-veined leaves: includes grasses
         and lilies and palms and orchids; divided into four
         subclasses or superorders: Alismatidae; Arecidae;
         Commelinidae; and Liliidae [syn: {Monocotyledones}, {class
         Monocotyledones}, {Monocotyledonae}, {class
         Monocotyledonae}, {class Liliopsida}]