To wash or groom oneself in order to be more attractive(verb)
To freshen, make fresh, revivify, make new.(verb)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "freshen up" in a sentence
"But, with a wink, he suggested the women be allowed to withdraw for a few minutes to freshen up before the orgy began."
"She was pretty sure her father simply wanted to congratulate her in person for the fine showing SFN had put in this afternoon, but she wanted to go home and freshen up before her date with Jason."
"P.S. Could you give me a copy or the original of Cruchard's biography; I have no draft of it and I want to reread it to freshen up MY IDEAL."