freshen vs wash up

freshen and wash up both are verbs.

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

As verbs, wash up is a hyponym of freshen; that is, wash up is a word with a more specific, narrower meaning than freshen:

Other hyponyms of freshen include lave.

freshen (verb)	wash up (verb)
make fresh again	wash one's face and hands
become or make oneself fresh again	wear out completely
make (to feel) fresh	be carried somewhere by water or as if by water
	wash dishes
	carry somewhere (of water or current or waves)