Dictionary
cu•mu•lus
Pronunciation: (kyOO'myu-lus), [key]—
n.,
—pl. -lus.
1. a heap; pile.
2. a cloud of a class characterized by dense individual elements in the form of puffs, mounds, or towers, with flat bases and tops that often resemble cauliflower: as such clouds develop vertically, they form cumulonimbus.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.