ofttimes vs oftentimes

ofttimes and oftentimes both are adverbs.

Word	Noun	Adjective	Verb	Adverb
ofttimes	No	No	No	Yes
oftentimes	No	No	No	Yes

As adverbs, ofttimes and oftentimes are synonyms defined as:

Other synonyms of ofttimes include frequently, oft, often.

ofttimes (adverb)	oftentimes (adverb)
many times at short intervals	many times at short intervals