mannerism vs specialness

mannerism and specialness both are nouns.

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

As nouns, specialness is a hypernym of mannerism; that is, specialness is a word with a broader meaning than mannerism:

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

Other hypernyms of mannerism include distinctiveness, peculiarity, speciality, specialty.

mannerism (noun)	specialness (noun)
a deliberate pretense or exaggerated display	a distinguishing trait
a behavioral attribute that is distinctive and peculiar to an individual	the quality of being particular and pertaining to a specific case or instance