a small planet and the farthest known planet from the sun; has the most elliptical orbit of all the planets; "Pluto was discovered by Clyde Tombaugh in 1930"
(Greek mythology) the god of the underworld in ancient mythology; brother of Zeus and husband of Persephone
(Greek mythology) 7 daughters of Atlas and half-sisters of the Pleiades; they nurtured the infant Dionysus and Zeus placed them among the stars as a reward
a measure of a person's intelligence as indicated by an intelligence test; the ratio of a person's mental age to their chronological age (multiplied by 100)