ring armor vs ring armour

ring armor and ring armour both are nouns.

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

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

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

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

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