unyieldingness vs adamance

unyieldingness and adamance both are nouns.

Word	Noun	Adjective	Verb	Adverb
unyieldingness	Yes	No	No	No
adamance	Yes	No	No	No

As nouns, unyieldingness and adamance are synonyms defined as:

unyieldingness and adamance: resoluteness by virtue of being unyielding and inflexible

Other synonyms of unyieldingness include obduracy.

unyieldingness (noun)	adamance (noun)
resoluteness by virtue of being unyielding and inflexible	resoluteness by virtue of being unyielding and inflexible