kindness vs favor

kindness and favor both are nouns.

Word	Noun	Adjective	Verb	Adverb
kindness	Yes	No	No	No
favor	Yes	No	Yes	No

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

kindness (noun)	favor (noun)
a kind act	an act of gracious kindness
the quality of being warmhearted and considerate and humane and sympathetic	souvenir consisting of a small gift given to a guest at a party
tendency to be kind and forgiving	an advantage to the benefit of someone or something
	an inclination to approve
	a feeling of favorable regard