Canis Major vs constellation

Canis Major and constellation both are nouns.

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

Canis Major (noun)	constellation (noun)
a constellation to the southeast of Orion; contains Sirius	an arrangement of parts or elements
	a configuration of stars as seen from the earth