from the species name (Xiphophorus) helleri, after C. Heller, 20th-c. aquarist
helleri in American English
(ˈheləˌrai, -ri)
noun
1.
a brightly colored, playful topminnow that is a hybrid of Xiphophorus helleri and X. maculatus, bred for aquariums
2.
swordtail
Word origin
[1905–10; ‹ NL helleri (of Heller), a specific epithet, after Carl Heller, 20th cent. tropical fish collector]This word is first recorded in the period 1905–10. Other words that entered Englishat around the same time include: Expressionism, cadre, persona, scrounge, thiamine