triangle/ˋtraI͵æŋgḷ; ˈtraIæŋɡ$l/n [C]1 a flat shape with three straight sides and three angles 三角形see box at见 SHAPE1 方框see picture at见 SHAPE1 图2 a small musical instrument shaped like a triangle. You hit it with a metal stick. 三角铁〔一种打击乐器〕—triangular /traIˋæŋgjəlɚ; traIˈæŋɡjələ or traIˈæŋɡjʊlə/adj