An Etymological Dictionary of the German Language/Annotated/oft
Appearance
oft, adverb, from the equivalent Middle High German oft, ofte, Old High German ofto, adverb, ‘often, frequently’; corresponding. to Gothic ufta, Old Icelandic opt, Anglo-Saxon oft, English oft (extended form often), Old Saxon oft, ofto, ‘often.’ These adverb forms seem to be petrified cases of an obsolete substantive or adjective participle; they have also been connected with the participle of the Sanscrit root uc, ‘to be fond of doing.’