CYCLOSTOME Meaning of CYCLOSTOME in English [ 'sʌɪklə(ʊ)stəʊm ]■ noun Zoology an eel-like jawless vertebrate with a round sucking mouth, such as a lamprey or hagfish.OriginC19: from cyclo- + Gk stoma 'mouth'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004