warranty vs assurance

warranty and assurance both are nouns.

Word	Noun	Adjective	Verb	Adverb
warranty	Yes	No	No	No
assurance	Yes	No	No	No

As nouns, assurance is a hypernym of warranty; that is, assurance is a word with a broader meaning than warranty:

warranty: a written assurance that some product or service will be provided or will meet certain specifications
assurance: a binding commitment to do or give or refrain from something

Other hypernyms of warranty include pledge.

warranty (noun)	assurance (noun)
a written assurance that some product or service will be provided or will meet certain specifications	freedom from doubt; belief in yourself and your abilities
	a statement intended to inspire confidence
	a binding commitment to do or give or refrain from something
	a British term for some kinds of insurance