fondness vs attachment

fondness and attachment both are nouns.

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

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

Other hyponyms of fondness include fond regard, protectiveness, regard, respect, soft spot.

fondness (noun)	attachment (noun)
a quality proceeding from feelings of affection or love	the act of fastening things together
a positive feeling of liking	the act of attaching or affixing something
a predisposition to like something	faithful support for a cause or political party or religion
	a supplementary part or accessory
	a connection that fastens things together
	a writ authorizing the seizure of property that may be needed for the payment of a judgment in a judicial proceeding
	a feeling of affection for a person or an institution