ring armour vs chain armor

ring armour and chain armor both are nouns.

Word	Noun	Adjective	Verb	Adverb
ring armour	Yes	No	No	No
chain armor	Yes	No	No	No

As nouns, ring armour and chain armor are synonyms defined as:

ring armour and chain armor: (Middle Ages) flexible armor made of interlinked metal rings

Other synonyms of ring armour include chain armour, chain mail, mail, ring armor, ring mail.

ring armour (noun)	chain armor (noun)
(Middle Ages) flexible armor made of interlinked metal rings	(Middle Ages) flexible armor made of interlinked metal rings