IRA FLATOW, HOST:
It's time for our monthly episode of Science Diction, where we explore the origins of scientific words with my guest Howard Markel, professor of history of medicine at the University of Michigan in Ann Arbor, also director of the Center for the History of Medicine there. He joins us WUOM. Welcome back, Howard.
HOWARD MARKEL: Good afternoon, Ira.
FLATOW: We have a very interesting word, or actually lab equipment today.
MARKEL: That we do. It's my favorite plate. It's the Petri dish.