relative atomic mass vs atomic weight

relative atomic mass and atomic weight both are nouns.

Word	Noun	Adjective	Verb	Adverb
relative atomic mass	Yes	No	No	No
atomic weight	Yes	No	No	No

As nouns, relative atomic mass and atomic weight are synonyms defined as:

relative atomic mass and atomic weight: (chemistry) the mass of an atom of a chemical element expressed in atomic mass units

Other synonyms of relative atomic mass include atomic mass.

relative atomic mass (noun)	atomic weight (noun)
(chemistry) the mass of an atom of a chemical element expressed in atomic mass units	(chemistry) the mass of an atom of a chemical element expressed in atomic mass units