"suit of clothing for women, consisting of pants and a matching or coordinating coat or jacket," 1966, contraction of pants suit (1964), from pants + suit (n.).
also cat-suit, "tight-fitting full-body garment," 1960, from cat (n.) + suit (n.). Perhaps so called because suitable for slinking.
"suit ill, be unfitting," 1520s, from mis- (1) "badly, wrongly" + become.
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