oft (adv.)

Old English oft "repeatedly, again and again, many times; frequently; under many circumstances," from Proto-Germanic *ufta- "frequently" (source also of Old Frisian ofta, Danish ofte, Old High German ofto, German oft, Old Norse opt, Gothic ufta "often"), a word of unknown origin, perhaps [Watkins] from a suffixed form of PIE root *upo "under."

Archaic or only poetic except in compounds (such as oft-told) and replaced by its derivative often. It also was an adjective in Middle English, "frequent, repeated." Related: Ofter; oftest.