prototypical

The story

1. Proto-Indo-European*per-der.?
2. Proto-Indo-European*pér
3. Proto-Indo-European*pró
4. Ancient Greekπρό (pró)
5. Ancient Greekπρῶτος (prôtos)
6. Ancient Greekπρωτο- (prōto-)
7. Proto-Indo-European*(s)tew-
8. Proto-Indo-European*(s)tewp-
9. Proto-Hellenic*túpt͏̌ō
10. Ancient Greekτῠ́πτω (tŭ́ptō)
11. Ancient Greekπρωτότυπος (prōtótupos)
12. Latinprōtotypu
13. Frenchprototype
14. Ancient Greekπρωτότυπος (prōtótupos)
15. Late Latinprototypon
16. Englishprototype
17. Proto-Indo-European*h₂el-
18. Proto-Indo-European*h₂élisder.?
19. English todayprototypical

From prototype + -ical.