a. [f. mod.L. citigrada, f. L. citus swift + gradus step: cf. F. citigrade.] lit. Moving swiftly; applied to a tribe of swift-moving spiders, Citigrada, and sbst. one of these.
1845. Darwin, Voy. Nat., viii. (1875), 160. A spider … which in its general appearance resembled a Citigrade.
