The story
- Proto-Indo-European*h₂ent-
- Proto-Indo-European*h₂énts
- Proto-Indo-European*h₂énti
- Ancient Greekᾰ̓ντῐ́ (ăntĭ́)
- Ancient Greekἀντι- (anti-)
- Englishanti-
- Englishant-
- Ancient Greekἕλμῐνς (hélmĭns)
- Englishhelminth
- Englishanthelmintic
- English today-antel
From anthelmintic (“against parasitic worms”), with simplification of the -nth- and truncation.
Etymology from Wiktionary, CC BY-SA 4.0.