antiagnostic

The story

1. Proto-Indo-European*h₂ent-
2. Proto-Indo-European*h₂énts
3. Proto-Indo-European*h₂énti
4. Ancient Greekᾰ̓ντῐ́ (ăntĭ́)
5. Ancient Greekἀντι- (anti-)
6. Englishanti-
7. Proto-Indo-European*né
8. Proto-Indo-European*n̥-
9. Proto-Hellenic*ə-
10. Ancient Greekᾰ̓- (ă-)
11. Proto-Indo-European*ǵneh₃-
12. Proto-Indo-European*ǵn̥h₃sḱéti
13. Proto-Hellenic*gignṓskō
14. Ancient Greekγῐγνώσκω (gĭgnṓskō)
15. Ancient Greekἄγνωστος (ágnōstos)
16. Ancient Greekἀ- (a-)
17. Englisha-
18. Proto-Indo-European*ǵneh₃-
19. Proto-Indo-European*ǵneh₃tis
20. Ancient Greekγνῶσις (gnôsis)
21. Ancient Greekγνωστῐκός (gnōstĭkós)
22. EnglishGnostic
23. Englishagnostic
24. English todayantiagnostic

From anti- + agnostic.