1. astronomy constellation in northern hemisphere: a zodiacal constellation of the northern hemisphere between Gemini and Leo
2. zodiac 4th sign of zodiac: the fourth sign of the zodiac, represented by a crab and lasting from approximately June 21 to July 22. Cancer is classified as a water sign, and its ruling planet is the Moon.
3. zodiac somebody born under Cancer sign: somebody whose birthday falls between June 21 and July 22
[Pre-12th century. < Latin (see cancer); from the constellation's sideways movement across the sky]
