SAPONACEOUS Meaning of SAPONACEOUS in English [ ˌsapə'neɪʃəs ]■ adjective resembling or containing soap; soapy.OriginC18: from mod. L. saponaceus (from L. sapo , sapon- 'soap') + -ous . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004