specialness vs foible

specialness and foible both are nouns.

Word	Noun	Adjective	Verb	Adverb
specialness	Yes	No	No	No
foible	Yes	No	No	No

As nouns, foible is a hyponym of specialness; that is, foible is a word with a more specific, narrower meaning than specialness:

specialness: a distinguishing trait
foible: a behavioral attribute that is distinctive and peculiar to an individual

Other hyponyms of specialness include idiosyncrasy, mannerism.

specialness (noun)	foible (noun)
a distinguishing trait	the weaker part of a sword's blade from the forte to the tip
the quality of being particular and pertaining to a specific case or instance	a behavioral attribute that is distinctive and peculiar to an individual
	a minor flaw or shortcoming in character or behavior.