Gemini (n.)

zodiac constellation, late Old English, from Latin gemini (plural of adjective geminus) "twins" (see geminate). Formerly also spelled gemeny, gemony, jeminy, etc. The twins are Castor and Pollux in Latin, which also are the names of the two brightest stars in the constellation; for their Greek name see Dioscuri. Meaning "a person born under the sign of Gemini" is recorded from 1894. As an oath, from 1660s (also found in Dutch and German), perhaps a corruption of Jesu (compare jiminy).