Guinea pepper gui·nea·pep·per uncommon noun 1. West African plant bearing pungent peppery seeds Synonymsgrains of paradiseGuinea grainsGuinea peppermelagueta pepperAframomum melegueta 2. tropical west African evergreen tree bearing pungent aromatic seeds used as a condiment and in folk medicine SynonymsGuinea peppernegro pepperXylopia aethiopica Related words Broader terms treeherb Parts XylopiaAframomum WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.