allopurinol UK /ˌæl.ə(ʊ)ˈpjʊə.ɹɪn.ɒl/US /ˌæl.oʊˈpjʊɹ.əˌnɔl/ noun1 •A synthetic drug which inhibits uric acid formation, used to treat gout and related conditions. formsallopurinols