varnish vs fixative

varnish and fixative both are nouns.

Word	Noun	Adjective	Verb	Adverb
varnish	Yes	No	Yes	No
fixative	Yes	No	No	No

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

varnish: a coating that provides a hard, lustrous, transparent finish to a surface
fixative: a varnish dissolved in alcohol and sprayed over pictures to prevent smudging

Other hyponyms of varnish include shellac, shellac varnish.

varnish (noun)	fixative (noun)
a coating that provides a hard, lustrous, transparent finish to a surface	a varnish dissolved in alcohol and sprayed over pictures to prevent smudging
	a compound (such as ethanol or formaldehyde) that fixes tissues and cells for microscopic study

varnish (verb)	fixative (verb)
cover with varnish