Old English fætt "fat, fatted, plump, obese," originally a contracted past participle of fættian "to cram, stuff," from Proto-Germanic *faitaz "fat" (cf. Old Frisian fatt, Old Norse feitr, Dutch vet, German feist), from PIE *poid- "to abound in water, milk, fat, etc." (cf. Greek piduein "to gush forth"), from root *peie- "to be fat, swell" (cf. Sanskrit payate "swells, exuberates," pituh "juice, sap, resin;" Lithuanian pienas "milk;" Greek pion "fat, wealthy;" Latin pinguis "fat").
Teen slang meaning "attractive, up to date" (also later