unparliamentary

The story

1. Proto-Indo-European*né
2. Proto-Indo-European*n̥-
3. Proto-Germanic*un-
4. Proto-West Germanic*un-
5. Old Englishun-
6. Middle Englishun-
7. Englishun-
8. Proto-Indo-European*per-
9. Proto-Indo-European*preh₂-
10. Proto-Hellenic*pərai
11. Ancient Greekπᾰρᾰ́ (părắ)
12. Ancient Greekπαρα- (para-)
13. Proto-Indo-European*gʷelH-
14. Proto-Hellenic*gʷəlnō
15. Ancient Greekβάλλω (bállō)
16. Ancient Greekπαραβάλλω (parabállō)
17. Ancient Greekπαραβολή (parabolḗ)
18. Latinparabola
19. Latinparabolāre
20. Old Frenchparler (to speak)
21. Old Frenchparlement
22. Middle Englishparlement
23. Englishparliament
24. Englishparliamentary
25. English todayunparliamentary

From un- + parliamentary.