noun
plural -cers
a serious disease caused by cells that are not normal and that can spread to one or many parts of the body [noncount]
[count] :something bad or dangerous that causes other bad things to happen - usually singular
Cancer
[noncount] :the fourth sign of the zodiac that comes between Gemini and Leo and has a crab as its symbol - see picture at zodiac
[count] :a person born under the sign of Cancer :a person born between June 22nd and July 22nd