round down vs round off

round down and round off both are verbs.

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

As verbs, round down and round off are synonyms defined as:

Other synonyms of round down include round, round out.

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