pole star vs Little Dipper

pole star and Little Dipper both are nouns.

Word	Noun	Adjective	Verb	Adverb
pole star	Yes	No	No	No
Little Dipper	Yes	No	No	No

pole star (noun)	Little Dipper (noun)
the brightest star in Ursa Minor; at the end of the handle of the Little Dipper; the northern axis of the earth points toward it	a cluster of seven stars in Ursa Minor; at the end of the dipper's handle is Polaris