In Slang “To Cap” Means “To Lie” but Why?

A Nevada high-schooler wonders about the slang terms cap meaning “to lie” and no cap, meaning I’m not lying. Many people associate it with the Future & Young Thug song “No Cap.” However, the expression goes back to the 1500s, when you might cap an anecdote, quotation, or verse as part of a verbal jousting game. By the 1800s, capping was a way of competing by telling a better joke than someone else, and by the 1940s, Black Americans were using the verb to cap when trading ever more exaggerated insults, otherwise known as the dozens or the dirty dozens. In that way, capping became a synonym for “stretching the truth.” This is part of a complete episode.