fondness vs tenderness

fondness and tenderness both are nouns.

Word	Noun	Adjective	Verb	Adverb
fondness	Yes	No	No	No
tenderness	Yes	No	No	No

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

Other hyponyms of fondness include uxoriousness.

As nouns, fondness and tenderness are synonyms defined as:

Other synonyms of fondness include affection, affectionateness, heart, philia, warmheartedness, warmness.

fondness (noun)	tenderness (noun)
a quality proceeding from feelings of affection or love	a tendency to express warm and affectionate feeling
a positive feeling of liking	a feeling of concern for the welfare of someone (especially someone defenseless)
a predisposition to like something	a positive feeling of liking
	warm compassionate feelings
	a pain that is felt (as when the area is touched)