neoplasm

(NEE-oh-PLA-zum) An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Neoplasms may be benign (not cancerous), or malignant (cancerous). Also called tumor.

Localized cell multiplication, forming a tumour. Generally the result of genetic transformation. Neoplasmic cells differ in structure and function from the original cell type.