willpower vs self-control

willpower and self-control both are nouns.

Word	Noun	Adjective	Verb	Adverb
willpower	Yes	No	No	No
self-control	Yes	No	No	No

As nouns, willpower and self-control are synonyms defined as:

willpower and self-control: the trait of resolutely controlling your own behavior

Other synonyms of willpower include possession, self-command, self-possession, self-will, will power.

willpower (noun)	self-control (noun)
the trait of resolutely controlling your own behavior	the act of denying yourself; controlling your impulses
	the trait of resolutely controlling your own behavior