An Etymological Dictionary of the German Language/Annotated/Faß
Faß, neuter, ‘vessel, cask, vat,’ from Middle High German vaȥ, Old High German faȥ(ȥȥ), neuter, ‘cask, vessel, chest’; corresponds to Middle Low German and Dutch vat, Anglo-Saxon fœt, ‘vessel, receptacle, chest’ (English vat), Old Icelandic fat, ‘cask.’ The primary signification of those cognates (pre-Teutonic podo-) may have been ‘receptacle,’ and since Fessel is an allied word, we have to postulate the meaning ‘to hold together’ for the Teutonic root fat. Lithuanian pũdas, ‘pot, vessel,’ would be in Gothic *fôta- instead of *fata-. Modern High German Gefäß is not an immediate derivative of Faß, because it assumes a Gothic *gafêti, neuter, See fassen, Fetzen, Fitze.