French polish vs French polish shellac

French polish and French polish shellac both are nouns.

Word	Noun	Adjective	Verb	Adverb
French polish	Yes	No	No	No
French polish shellac	Yes	No	No	No

As nouns, French polish and French polish shellac are synonyms defined as:

French polish and French polish shellac: a varnish for wood consisting of shellac dissolved in alcohol

French polish (noun)	French polish shellac (noun)
a varnish for wood consisting of shellac dissolved in alcohol	a varnish for wood consisting of shellac dissolved in alcohol
the glaze produced by repeated applications of French polish shellac