pretending vs mannerism

pretending and mannerism both are nouns.

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

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

Other hyponyms of pretending include appearance, show, make-believe, pretend, affectation, affectedness, pose, charade, masquerade.

pretending (noun)	mannerism (noun)
the act of giving a false appearance	a deliberate pretense or exaggerated display
	a behavioral attribute that is distinctive and peculiar to an individual