An Etymological Dictionary of the German Language/Annotated/fassen

by Friedrich Kluge

fassen, verb, ‘to hold, grasp, comprehend,’ (reflexive) ‘to make up one's mind,’ from Middle High German vaȥȥen, Old High German faȥȥôn, ‘to handle, seize, load, pack, arm oneself, dress, go’; it seems to be a combination of two or more really different roots. Compare Old Icelandic fǫt, neuter plural, ‘garments’ (Gothic *fata, ‘garments,’ may be deduced from Spanish hato, Portuguese fato, ‘stock of clothes, wardrobe’); the West Teutonic fat (see Faß), has not this meaning, but Middle High German (Old High German) vaȥȥen, ‘to dress oneself, points that way. In the sense ‘to seize,’ the word may be connected with Faß, literally ‘engulphing,’ from which the meaning ‘to load’ would be evolved. In the sense of ‘to go’ (sich vaȥȥen, Middle High German) it must probably be connected with Fuß, or more closely with Anglo-Saxon fœt, ‘step.’ See Fetzen, Fitze.