THE FIRST WORD

zoonosis
"When a pathogen leaps from some nonhuman animal into a person, and succeeds there in establishing itself as an infectious presence, sometimes causing illness or death, the result is a zoonosis," Mr. Quammen writes...
Zoonosis comes from Greek roots meaning "animal" and "disease." Other unusual zoo- words include zoochore (a plant whose seeds are spread by animals), zoophagan (a carnivorous animal) and zoomancy (divination by watching animals).