double-barrelled

Universal Words (BrE) (AmE double-barreled) adjective [usuallybeforenoun] 1 (of a gun) having two BARRELS (= places where the bullets come out) 2 (BrE) (of a family name) having two parts, sometimes joined by a HYPHEN, for example 'Day-Lewis' 3 (AmE) (of a plan, etc.) having two parts, and therefore likely to be effective