brush up brus·hup uncommon informal verb 1. refresh one''s memory “I reviewed the material before the test” Synonymsreviewbrush uprefresh 2. bring to a highly developed, finished, or refined state “polish your social manners” Synonymspolishroundround offpolish upbrush up Related words Word family polishrefresherbrushupreview Broader terms perfectremember WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.