misdiagnose

The story

1. Proto-Indo-European*mey-?
2. Proto-Indo-European*meyth₂-
3. Proto-Germanic*missaz
4. Proto-Germanic*missa-
5. Proto-West Germanic*missa-
6. Old Englishmis-
7. Middle Englishmys-
8. Englishmis-
9. Proto-Indo-European*dwóh₁
10. Proto-Indo-European*trísinflu.
11. Proto-Indo-European*dwís
12. Ancient Greekδιά (diá)
13. Ancient Greekδια- (dia-)
14. Proto-Indo-European*ǵneh₃-
15. Proto-Indo-European*ǵn̥h₃sḱéti
16. Proto-Hellenic*gignṓskō
17. Ancient Greekγῐγνώσκω (gĭgnṓskō)
18. Ancient Greekδῐαγῐγνώσκω (dĭagĭgnṓskō)
19. Ancient Greekδῐᾰ́γνωσῐς (dĭắgnōsĭs)
20. Latindiagnōsis
21. Englishdiagnosisbf.
22. Englishdiagnose
23. English todaymisdiagnose

From mis- + diagnose.