v 1. to look attractive. Always used to refer to someone who doesn't usually appear attractive, but becomes attractive when they make an effort, e.g. by dressing nicely, putting on makeup, etc. ("She's dressed in sweatpants now, but boy can she clean up good!") Submitted by Gil C, Chicago, IL, USA, 07-12-2002.
CLEAN UP GOOD
Meaning of CLEAN UP GOOD in English
Slang English vocab. Английский сленговый словарь. 2012