quasar vs quasi-stellar radio source

quasar and quasi-stellar radio source both are nouns.

Word	Noun	Adjective	Verb	Adverb
quasar	Yes	No	No	No
quasi-stellar radio source	Yes	No	No	No

As nouns, quasar and quasi-stellar radio source are synonyms defined as:

quasar and quasi-stellar radio source: a starlike object that may send out radio waves and other forms of energy; many have large red shifts

quasar (noun)	quasi-stellar radio source (noun)
a starlike object that may send out radio waves and other forms of energy; many have large red shifts	a starlike object that may send out radio waves and other forms of energy; many have large red shifts