freshen up vs refresh

freshen up and refresh both are verbs.

Word	Noun	Adjective	Verb	Adverb
freshen up	No	No	Yes	No
refresh	No	No	Yes	No

As verbs, freshen up and refresh are synonyms defined as:

Other synonyms of freshen up include freshen, refreshen.

freshen up (verb)	refresh (verb)
become or make oneself fresh again	make fresh again
make brighter and prettier	become or make oneself fresh again
	make (to feel) fresh
	refresh one's memory