OCEANARIUM Meaning of OCEANARIUM in English [ ˌəʊʃə'nɛ:rɪəm ]■ noun ( plural ~s or oceanaria -rɪə ) a large seawater aquarium.Origin1940s: from ocean , on the pattern of aquarium . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004