late O.E. smeart "sharp, severe, stinging," related to smeortan (see smart
(v.)). Meaning "quick, active, clever" is attested from c.1300, probably from the notion of "cutting" wit, words, etc.; meaning "trim in attire" first attested 1718, "ascending from the kitchen to the
drawing-room c.1880." [Weekley] In ref. to devices, "behaving as though guided by intelligence" (e.g. smart bomb) first attested 1972. Smarts "good sense, intelligence," is first recorded 1968. Smart aleck is from 1865, perhaps in allusion to Aleck Hoag, notorious pimp, thief, and confidence man in New York City in early 1840s. Smart cookie is from 1948; smarty-pants first attested 1941.