the disease caused by an uncontrolled division of abnormal cells in a part of the body."he's got cancer"a malignant growth or tumor resulting from the division of abnormal cells.plural noun: cancers"most skin cancers are curable"synonyms: malignant growth, cancerous growth, tumor, malignancy; Morea practice or phenomenon perceived to be evil or destructive and hard to contain or eradicate."racism is a cancer sweeping across Europe"synonyms: evil, blight, scourge, poison, canker, plague; archaicpestilence"the cancer of slavery spread across the continent"