furthermore UK /ˈfɜː(ɹ).ðə(ɹ)ˌmɔː(ɹ)/US /ˈfɝ.ðɚˌmoɹ/ adverb1 •In addition; besides; further; what's more (i.e. to denote additional information).He skillfully took charge of the event, and furthermore, he stayed late after it to clean up.He claimed further(more) that he was not even in town the day the murder occured.