clean out verb4 •To clean, especially to tidy by removing the contents.Clean out your purse and at least get rid of all the trash you're hauling around. •(slang) To take all money or possessions from.The divorce cleaned him out. •To defeat, to cause to wash out. •(slang, old-fashioned) To hit or strike (someone); to beat up.could have cleaned him out with an uppercut to the side of his head. — 2000 formscleaned out · cleaning out · cleans out