any of various butterflies of the genus Papilio and related genera, esp P. machaon of Europe, having a tail-like extension of each hind wing: family Papilionidae
2.
the forked tail of a swallow or similar bird
3. short for swallow-tailed coat
swallowtail in American English
(ˈswɑloʊˌteɪl)
noun
1.
something having a forked shape like that of a swallow's tail
2.
any of a large family (Papilionidae) of brightly colored butterflies found worldwide, having the hind wings extended in taillike points