clutch bag vs pocketbook

clutch bag and pocketbook both are nouns.

Word	Noun	Adjective	Verb	Adverb
clutch bag	Yes	No	No	No
pocketbook	Yes	No	No	No

As nouns, pocketbook is a hypernym of clutch bag; that is, pocketbook is a word with a broader meaning than clutch bag:

clutch bag: a woman's strapless purse that is carried in the hand
pocketbook: a container used for carrying money and small personal items or accessories (especially by women)

Other hypernyms of clutch bag include bag, handbag, purse.

clutch bag (noun)	pocketbook (noun)
a woman's strapless purse that is carried in the hand	a container used for carrying money and small personal items or accessories (especially by women)
	pocket-sized paperback book
	a pocket-size case for holding papers and paper money
	your personal financial means