1
general::
Phrase(s): brush up (on something)
to improve one’s knowledge of something or one’s ability to do something. • I need to brush up on my German. • My German is weak. I had better brush up., Phrase(s): brush something up
to improve one’s knowledge of something or one’s ability to do something. (See also brush up (on something).) • I need to brush my French up a little bit. • I need to brush up my French.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. Clean, refurbish, as in We plan to get the house brushed up in time for the party. [c. 1600] 2. Also, brush up on. Review, refresh one's memory, as in Nell brushed up on her Spanish before going to Honduras, or I'm brushing up my knowledge of town history before I speak at the club. [Late 1700s]
American Heritage Idioms