English
fatheaded
From fat + headed.
Proto-West Germanic *fait
Proto-West Germanic *faitijan ‘to make fat’
Proto-West Germanic *faitid ‘fatted’
Old English fǣtt ‘fatted’
Middle English fat ‘fattened’
English fat
Today it means
adj Characteristic of a fathead; stupid
Language periods are conventional ranges, not dates for this word.
Etymograph / fatheaded