swordtail noun2 •One of many species of freshwater fish, in genus Xiphophorus, others of which are called platyfish.There were all kinds - Swordtails, Guppies, Platys, Terras [sic], Neons, Cichlids, Labyrinth and Paradise fish, and every variety of exotic Goldfish. — 1954 •Any of various papilionid butterflies that have a long sword-like projection from the tornal section of each hindwing. formsswordtails
