complacence vs complacency

complacence and complacency both are nouns.

Word	Noun	Adjective	Verb	Adverb
complacence	Yes	No	No	No
complacency	Yes	No	No	No

As nouns, complacence and complacency are synonyms defined as:

complacence and complacency: the feeling you have when you are satisfied with yourself

Other synonyms of complacence include self-complacency, self-satisfaction.

complacence (noun)	complacency (noun)
the feeling you have when you are satisfied with yourself	the feeling you have when you are satisfied with yourself