Idioms and Phrases with keep it up
keep it up
Continue to do or maintain something, as in They were playing loud music, and they kept it up all night long. [Mid-1700s] Also see keep up, def. 4.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.