An Etymological Dictionary of the German Language/Annotated/taugen
taugen, verb, ‘to be of use, be good or fit for,’ from Middle High German tugen, Old High German tugan (present singular touc), preterite present, ‘to be capable, useful, suitable, to be of use, to suit.’ Corresponding to Old Saxon dugan, ‘to be capable, be of use,’ Dutch deugen, ‘to be of use,’ Anglo-Saxon dugan, Old Icelandic duga, Gothic dugan, ‘to be fit, of use’ The Teutonic verbal root dug (daug) might, like Lithuanian daúg, ‘much,’ daúksinti, ‘to increase,’ point to Aryan dhugh (Greek τύχη, ‘fortune,’ τυγχάνω, ‘I am fortunate’?). To this are allied tüchtig and Tugend.