frugal vs scotch

frugal is not a noun while scotch is a noun.

Word	Noun	Adjective	Verb	Adverb
frugal	No	Yes	No	No
scotch	Yes	Yes	Yes	No

As adjectives, frugal and scotch are synonyms defined as:

Other synonyms of frugal include economical, sparing, stinting.

frugal (noun)	scotch (noun)
	a slight surface cut (especially a notch that is made to keep a tally)

frugal (adjective)	scotch (adjective)
avoiding waste	avoiding waste

frugal (verb)	scotch (verb)
	make a small cut or score into
	hinder or prevent (the efforts, plans, or desires) of