cross out verb4 •To strike out (something); to draw a line through (something).If you make a mistake, just cross it out. •(slang) To lie to or betray (someone); to deceive or scam (someone). •To disrespect (someone) by covering up or painting over their graffiti, especially their name. •(slang) To kill; X out. formscrossed out · crossing out · crosses out