in reference to clouds, "of the nature of cumulus clouds," 1815, see cumulo- + -ous.
Entries linking to cumulous
cumulo- n.
word-forming element meaning "like or of the nature of cumulus clouds," 1887, from cumulus. Cumulo-stratus is from 1803; Cumulo-nimbus is attested by 1859.
-ous
word-forming element making adjectives from nouns, meaning "having, full of, having to do with, doing, inclined to," from Old French -ous, -eux, from Latin -osus (compare -ose (1)). In chemistry, "having a lower valence than forms expressed in -ic."