clean up act
Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Encyclopedia.
clean up (one's) act
To improve one's behavior. After I got in yet another fight at school, the headmaster told me that I had to clean up my act or else I'd be expelled.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
clean up (one's) actSlang
To improve one's behavior or performance.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.