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"person with a strong desire to dress in clothing of the opposite sex," 1922, from German Transvestit (1910), coined from Latin trans- "across" (see trans-) + vestire "to dress, to clothe" (see wear (v.)). Cf. also travesty, which is the same word, older, and passed through French and Italian. Shortened form trannie first recorded 1983 (in 1960s this was used as a slang shortening of transistor radio). Transvestism is first attested 1928.
transvestite trans·ves·tite (trāns-věs'tīt', trānz-)
One who practices transvestism.