ˈsirēəs noun
Usage: capitalized
Etymology: New Latin, from Latin, wax candle, from cera wax, probably from Greek kēros; akin to Lithuanian korys honeycomb
: a genus of cacti of the western United States and tropical America including mostly erect and columnar much-branched forms with spiny ribs and large elongated nocturnal flowers usually borne singly along the ribs — compare night-blooming cereus , saguaro