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pet form of masc. proper names Edward, Edmund, and Theodore; meaning "women's undergarment" (with lower-case t-) is recorded from 1924, of unknown origin, perhaps from some fancied resemblance to a teddy bear (q.v.), a theory that dates to 1929. In British slang phrase teddy boy (1954) it is short for Edward, from the preference of such youths for Edwardian styles (1901-10). Teddies (probably from Teddy Roosevelt) was one of the names given to U.S. troops in France in 1917.
the family in America originally bore the name Van Roosevelt, "of the field of roses," descriptive of their estates in Holland. Claes Martenszen Van Rosenvelt, born August 1649, emigrated to New Amsterdam. His son (1653) and all his descendants dropped the "Van." Related: Rooseveltian.
A one-piece women's undergarment serving as both chemise and panties
[1924+; perhaps fr teddy bear]