oleiferous Syllabification: (o·le·if·er·ous)Pronunciation: /ˌōlēˈifərəs/Definition of oleiferous adjective Botany (of seeds, glands, etc.) producing oil. Origin: early 19th century: from Latin oleum 'oil' + -ferousoleiferous in other Oxford dictionaries Definition of oleiferous in the British & World English dictionary