1. (n.) A genus of decapod Crustacea, including some of the most common shore crabs of Europe and North America, as the rock crab, Jonah crab, etc. See Crab.

2. (n.) The fourth of the twelve signs of the zodiac. The first point is the northern limit of the sun's course in summer; hence, the sign of the summer solstice. See Tropic.

3. (n.) A northern constellation between Gemini and Leo.

4. (n.) Formerly, any malignant growth, esp. one attended with great pain and ulceration, with cachexia and progressive emaciation. It was so called, perhaps, from the great veins which surround it, compared by the ancients to the claws of a crab. The term is now restricted to such a growth made up of aggregations of epithelial cells, either without support or embedded in the meshes of a trabecular framework.

benign tumor blast blight callosity callus canker carcinoma corn cyst dry rot excrescence fungosity fungus growth intumescence malignant growth metastatic tumor mildew mold mole morbid growth moth moth and rust must neoplasm nevus nonmalignant tumor outgrowth pest proud flesh rot rust sarcoma smut tumor verruca wart wen worm