Any substance that produces cancer; as, to test for carcinogens in the drinking water.

Chemicals, ionizing radiation, and viruses that cause or promote the development of cancer. See cancer. Compare mutagen, teratogen.

This is an agent that may cause cancer. Ionizing radiations are physical carcinogens; there are also chemical and biologic carcinogens. Biologic carcinogens may be external (such as a virus) or internal (such as genetic defects).

an agent that incites carcinoma (cancer) or other malignancy.