A lasso or lazo (/ ˈ l æ s oʊ / or / l æ ˈ s uː /), also called in Mexico reata and la reata, [1] [2] and in the United States riata or lariat [3] (from Mexican Spanish, lasso for roping cattle), [4] is a loop of rope designed as a restraint to be thrown around a target and tightened when pulled.