polish up vs round off

polish up and round off both are verbs.

Word	Noun	Adjective	Verb	Adverb
polish up	No	No	Yes	No
round off	No	No	Yes	No

As verbs, polish up and round off are synonyms defined as:

polish up and round off: bring to a highly developed, finished, or refined state

Other synonyms of polish up include brush up, polish, round.

polish up (verb)	round off (verb)
bring to a highly developed, finished, or refined state	express as a round number
	make round
	bring to a highly developed, finished, or refined state