CACTI
CACTUS
cactus
(noun) any succulent plant of the family Cactaceae native chiefly to arid regions of the New World and usually having spines
Source: WordNet® 3.1
Noun
cacti
plural of cactus
Source: Wiktionary
CACTUS
Cac"tus, n. ; pl. E. Cactuses, Cacti (-ti). Etym: [L., a kind of
cactus, Gr. (Bot.)
Definition: Any plant of the order Cactacæ, as the prickly pear and the
night-blooming cereus. See Cereus. They usually have leafless stems
and branches, often beset with clustered thorns, and are mostly
natives of the warmer parts of America. Cactus wren (Zoöl.), an
American wren of the genus Campylorhynchus, of several species.
Source: Webster’s Unabridged Dictionary 1913 Edition