A Transvestite is, literally, one who crossdresses, who wears articles of clothing intended for the opposite sex.
The term was derived from Transvestism, which is attributed to Dr. Mangus Hirshchfeld, ca. 1919. Transvestite, (and the associated abbreviation "TV" or less commonly "XV") was a commonly-used label of self-identity up through the mid 1980s. The term deprecated as the term Crossdresser gained popularity.
In the 1980s and 1990s some considered the term "Transvestite" to have more of a sexual or arousal connotation as did "Crossdresser" and other related terms.
To the members of the TG Community, the term is now considered anachronistic. It does appear in clinical literature in the form of "Fetishistic Transvestite" as Fetishistic Transvestism is still an accepted clinical term and is one of the current classifications listed in the DSM 5.
Some individuals do still identify with this term as their primary label of self-identity.