cosmic microwave background radiation vs CMBR

cosmic microwave background radiation and CMBR both are nouns.

Word	Noun	Adjective	Verb	Adverb
cosmic microwave background radiation	Yes	No	No	No
CMBR	Yes	No	No	No

As nouns, cosmic microwave background radiation and CMBR are synonyms defined as:

cosmic microwave background radiation and CMBR: (cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2.725 kelvin

Other synonyms of cosmic microwave background radiation include CBR, CMB, cosmic background radiation, cosmic microwave background.

cosmic microwave background radiation (noun)	CMBR (noun)
(cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2.725 kelvin	(cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2.725 kelvin