VII vs septenary

VII and septenary both are nouns.

Word	Noun	Adjective	Verb	Adverb
VII	Yes	No	No	No
septenary	Yes	No	No	No

As nouns, VII and septenary are synonyms defined as:

Other synonyms of VII include 7, heptad, septet, seven, sevener.

VII (noun)	septenary (noun)
the cardinal number that is the sum of six and one	the cardinal number that is the sum of six and one