blazonry vs coat of arms

blazonry and coat of arms both are nouns.

Word	Noun	Adjective	Verb	Adverb
blazonry	Yes	No	No	No
coat of arms	Yes	No	No	No

As nouns, blazonry and coat of arms are synonyms defined as:

blazonry and coat of arms: the official symbols of a family, state, etc.

Other synonyms of blazonry include arms, blazon.

blazonry (noun)	coat of arms (noun)
the official symbols of a family, state, etc.	the official symbols of a family, state, etc.