Pronunciation: ( jem'u-nī", -nē),[key] —n.pl., —gen.Gem•i•no•rumPronunciation: (jem"u-nôr'um, -nōr'-)[key]for 1. 1. Astron.the Twins, a zodiacal constellation between Taurus and Cancer containing the bright stars Castor and Pollux.
2. Astrol. a. the third sign of the zodiac: the mutable air sign. See illus. under zodiac. b. a person born under this sign, usually between May 21st and June 20th.
3. a two-person U.S. spacecraft designed for orbital rendezvous and docking: used in 1965–66 in various experiments preparatory to a landing on the moon.