ALLIACEOUS Meaning of ALLIACEOUS in English [ ˌalɪ'eɪʃəs ]■ adjective Botany relating to or denoting plants of a group that comprises the onions and other alliums.OriginC18: from L. allium 'garlic' + -aceous . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004