The story
- Proto-Indo-European*né
- Proto-Indo-European*n̥-
- Proto-Germanic*un-
- Proto-West Germanic*un-
- Old Englishun-
- Middle Englishun-
- Englishun-
- Middle Englishentanglen
- Englishentangle
- Englishentangleable
- English todayunentangleable
From un- + entangleable.
Etymology from Wiktionary, CC BY-SA 4.0.