The story
- Proto-Indo-European*kʷetwṓr
- Proto-Germanic*fedwōr
- Proto-Indo-European*déḱm̥
- Proto-Indo-European*déḱm̥-t(-s)
- Proto-Germanic*tegun(dz)
- Proto-Germanic*tigiwiz
- Proto-Germanic*fedwōr tigiwiz
- Proto-West Germanic*feuwar tigiwi
- Old Englishfēowertiġ
- Middle Englishfourty
- Englishforty
- Old English*rodd
- Middle Englishrodde
- Englishrod
- English todayforty-rod
From forty + rod, a measure of distance, suggesting whiskey so strong it can affect one from 200 meters away.
Etymology from Wiktionary, CC BY-SA 4.0.