interdimensional

The story

1. Proto-Indo-European*h₁én
2. Proto-Indo-European*h₁n̥tér
3. Proto-Italic*n̥ter
4. Latininter
5. Latininter-
6. Englishinter-
7. Proto-Indo-European*dwóh₁
8. Proto-Indo-European*trísinflu.
9. Proto-Indo-European*d(w)is-
10. Proto-Italic*dis-
11. Latindis-
12. Proto-Indo-European*med-
13. Proto-Indo-European*meh₁-
14. Proto-Italic*mētis
15. Latinmētior
16. Latindīmētior
17. Latindīmēnsiō
18. Englishdimension
19. Proto-Indo-European*h₂el-
20. Proto-Indo-European*h₂élisder.?
21. Englishdimensional
22. English todayinterdimensional

From inter- + dimensional.