carcinoma UK /ˌkɑːsɪˈnəʊmə/US /ˌkɑɹsɪˈnoʊmə/ noun2 •An invasive malignant tumour derived from epithelial tissue that tends to metastasize to other areas of the body. •(no longer used) A form of cancer; (uncountable) cancer in general as a disease. formscarcinomas · carcinomata