carcinogen

carcinogens

A carcinogen is anything that causes cancer. Cigarette smoke, car exhaust, asbestos: all of these are known carcinogens. Don't even ask about the ones we don't know about...

When you see the suffix "-gen" you know you're dealing with something that produces, causes, or generates something. Think of the Book of Genesis, or the beginning of all things. "Carcinoma," the name of a specific type of cancer, comes from the Greek karkinos, which means "crab" and "ulcer," as well as the animal associated with the astrological sign of Cancer. So you can see that carcinogen simply means "generating cancer."