Triangle (2009 film) definition

(1) A percussion instrument consisting of a metal bar bent in the shape of an open triangle

(2) Any of various triangular drafting instruments used to draw straight lines at specified angles

(3) A small northern constellation near Perseus between Andromeda and Aries

(4) A three-sided polygon

(5) Something approximating the shape of a triangle

"The coastline of Chile and Argentina and Brazil forms two legs of a triangle"