purse vs round off

purse is a noun but round off is not a noun.

Word	Noun	Adjective	Verb	Adverb
purse	Yes	No	Yes	No
round off	No	No	Yes	No

As verbs, round off is a hypernym of purse; that is, round off is a word with a broader meaning than purse:

Other hypernyms of purse include round, round out.

purse (noun)	round off (noun)
a container used for carrying money and small personal items or accessories (especially by women)
a small bag for carrying money
a sum of money offered as a prize
a sum of money spoken of as the contents of a money purse

purse (verb)	round off (verb)
contract one's lips into a rounded shape	express as a round number
gather or contract into wrinkles or folds; pucker	make round
	bring to a highly developed, finished, or refined state