freshen vs renew

freshen and renew both are verbs.

Word	Noun	Adjective	Verb	Adverb
freshen	No	No	Yes	No
renew	No	No	Yes	No

As verbs, renew is a hypernym of freshen; that is, renew is a word with a broader meaning than freshen:

freshen: make (to feel) fresh
renew: reestablish on a new, usually improved, basis or make new or like new

Other hypernyms of freshen include regenerate.

freshen (verb)	renew (verb)
make fresh again	cause to appear in a new form
become or make oneself fresh again	reestablish on a new, usually improved, basis or make new or like new
make (to feel) fresh