The story
- Proto-Indo-European*né
- Proto-Indo-European*n̥-
- Proto-Germanic*un-
- Proto-West Germanic*un-
- Old Englishun-
- Middle Englishun-
- Englishun-
- Englishbackable
- English todayunbackable
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: That cannot or should not be backed, or supported in a contest, especially because the odds are unreasonably low. Full definition →
Etymology from Wiktionary, CC BY-SA 4.0.