What's the "een" in Halloween?
late 14c., from Old French contagion, from Latin contagionem (nominative contagio) "a touching, contact, contagion," related to contingere "touch closely" (see contact (n.)).
contagion con·ta·gion (kən-tā'jən)n.
Disease transmission by direct or indirect contact.
A disease that is or may be transmitted by direct or indirect contact; a contagious disease.
The transmission of an infectious disease resulting from direct or indirect contact between individuals or animals.
A disease that is transmitted in this way.
The agent that causes a contagious disease, such as a bacterium or a virus.