ne plus ultra vs flawlessness

ne plus ultra and flawlessness both are nouns.

Word	Noun	Adjective	Verb	Adverb
ne plus ultra	Yes	No	No	No
flawlessness	Yes	No	No	No

As nouns, ne plus ultra and flawlessness are synonyms defined as:

ne plus ultra and flawlessness: the state of being without a flaw or defect

Other synonyms of ne plus ultra include perfection.

ne plus ultra (noun)	flawlessness (noun)
the state of being without a flaw or defect	the state of being without a flaw or defect