cumulus
cu.mu.lus \-l*s\ \-.li-, -.le-\ n or cu.mu.li [L] [NL, fr. L] pl 1: HEAP, ACCUMULATION 2: a massy cloud form having a flat base and rounded outlines often piled u p like a mountain
Webster's English Dictionarycu.mu.lus \-l*s\ \-.li-, -.le-\ n or cu.mu.li [L] [NL, fr. L] pl 1: HEAP, ACCUMULATION 2: a massy cloud form having a flat base and rounded outlines often piled u p like a mountain