What it means
The ending in words for things that create something. A pathogenPATH-uh-jenA germ, such as a bacterium, virus, fungus or parasite, that can cause disease.path/o disease-gen something that producesFull entry produces disease, an allergenAL-er-jenA substance that triggers an allergic reaction in a person whose immune system is sensitive to it.all/o other-gen something that producesFull entry produces an allergy, an antigenAN-tih-jenA substance, often a protein on a germ or cell, that the immune system recognizes and responds to.anti- against (short for antibody)-gen something that producesFull entry causes the body to make antibodies, and a carcinogen causes cancer. The related endings -genic (producing, as in carcinogenic) and -genesis (formation, as in osteogenesis) come from the same root.