tenableness vs tenability

tenableness and tenability both are nouns.

Word	Noun	Adjective	Verb	Adverb
tenableness	Yes	No	No	No
tenability	Yes	No	No	No

As nouns, tenableness and tenability are synonyms defined as:

tenableness and tenability: the quality of being plausible or acceptable to a reasonable person

Other synonyms of tenableness include reasonableness.

tenableness (noun)	tenability (noun)
the quality of being plausible or acceptable to a reasonable person	the quality of being plausible or acceptable to a reasonable person