Sagittarius vs doer

Sagittarius and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sagittarius	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of Sagittarius; that is, doer is a word with a broader meaning than Sagittarius:

Sagittarius: (astrology) a person who is born while the sun is in Sagittarius
doer: a person who acts and gets things done

Other hypernyms of Sagittarius include actor, worker.

Sagittarius (noun)	doer (noun)
type genus of the Sagittariidae	a person who acts and gets things done
the ninth sign of the zodiac; the sun is in this sign from about November 22 to December 21
a large zodiacal constellation in the Southern Hemisphere; between Scorpius and Capricornus
(astrology) a person who is born while the sun is in Sagittarius