Definition of Gemini
1
: the third zodiacal constellation that is pictorially represented as the twins Castor and Pollux sitting together, that is visible in the sky on the opposite side of the Milky Way from Taurus and Orion, and that is located between Cancer and Taurus in the zodiac
2 a
: the third sign of the zodiac in astrology — see Signs of the Zodiac Table
b
: one born under the sign of Gemini
