The story
- Proto-Indo-European · inherited from*pleh₁-“to fill”
- Old English · inherited fromful
- Middle English · inherited fromunfulle“incomplete”
- English todayunfull
From Middle English unfulle (“incomplete”), from un- (prefix meaning ‘not’) + ful (“filled to capacity, full; complete, whole”) (from Old English ful, full (“filled, full; complete, entire”), ultimately from Proto-Indo-European *pleh₁- (“to fill”)). The English word is analysable as un- (prefix meaning ‘not’) + full.
Words from the same roots
Old Englishful all →
foulFulfordFulwoodFulwellfoumartFulbeckFulbrook
Proto-Indo-European*pleh₁- all →
publiccompletecomplypolyglotnonplussedpleromamaniplenonplusplebiscitumplethoricallypluri-
Etymology from Wiktionary, CC BY-SA 4.0.