Arecidae

n. 1. 1 one of four subclasses or superorder of Monocotyledones; comprises about 6400 species in 5 families of trees and shrubs and terrestrial herbs and a few free-floating aquatics including: Palmae; Araceae; Pandanaceae: and Lemnaceae.
Syn. -- subclass Arecidae [ WordNet 1.5 ]