anorthoscope

The story

1. Proto-Indo-European*né
2. Proto-Indo-European*n̥-
3. Proto-Hellenic*ə-
4. Ancient Greekᾰ̓- (ă-)
5. Ancient Greekἀν- (an-)
6. Englishan-
7. Proto-Indo-European*h₃er-
8. Proto-Indo-European*dʰeh₁-
9. Proto-Indo-European*h₃érdʰeti?
10. Proto-Indo-European*h₃erdʰ-
11. Proto-Hellenic*ortʰwós
12. Ancient Greekὀρθός (orthós)
13. Englishortho-
14. Proto-Indo-European*speḱ-
15. Proto-Indo-European*spéḱyeti
16. Proto-Hellenic*sképt͏̌omai
17. Ancient Greekσκέπτομαι (sképtomai)
18. Ancient Greekσκοπός (skopós)
19. Ancient Greekσκοπέω (skopéō)
20. English todayanorthoscope

From an- + ortho- + -scope.