can·cer 
(kănsər)
(kănsər)n.
1.
a. Any of various malignant neoplasms characterized by the proliferation of anaplastic cells that tend to invade surrounding tissue and metastasize to new body sites.
b. The pathological condition characterized by such growths.
2. A pernicious, spreading evil: A cancer of bigotry spread through the community.
[Middle English; see CANKER.]
cancer·ous (kănsər-əs) adj.