Pluto (Noun) — A small planet and the farthest known planet from the sun; it has the most elliptical orbit of all the planets. ex. "Pluto was discovered by Clyde Tombaugh in 1930"
Pluto (Noun) — A cartoon character created by Walt Disney.
Pluto (Noun) — (Greek mythology) the god of the underworld in ancient mythology; brother of Zeus and husband of Persephone.