Pronunciation: (pī'sēz, pis'ēz),[key] —n., —gen.Pis•ci•umPronunciation: (pish'ē-um),[key]for 1. 1. Astron.the Fishes, a zodiacal constellation between Aries and Aquarius.
2. Astrol. a. the twelfth sign of the zodiac: the mutable water sign. See illus. under zodiac. b. a person born under this sign, usually between February 19th and March 20th.
3. the class of vertebrates comprising the fish and sometimes including, in certain classifications, the cyclostomes.