Ursa Major vs constellation

Ursa Major and constellation both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ursa Major	Yes	No	No	No
constellation	Yes	No	No	No

Ursa Major (noun)	constellation (noun)
a constellation outside the zodiac that rotates around the North Star, also known as the Great Bear or Charles' Wain	an arrangement of parts or elements
	a configuration of stars as seen from the earth