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English definition of “triangle”


noun [C]     /ˈtraɪ.æŋ.ɡl̩/
B2 a flat shape with three straight sides : an equilateral / isosceles triangleGeometrical shapesSpherical, circular and annular objects anything that has three straight sides : Which earrings did you buy in the end - the triangles or the circles ?Geometrical shapesSpherical, circular and annular objects a musical instrument consisting of a thin metal bar bent into a triangle shape that is hit with a metal bar to make a sound Percussion instruments US for set squareGeometrical and mathematical instruments (also frame) a three-sided frame for arranging the balls at the start of a game of billiards, pool , etc.Snooker, pool and billiards
(Definition of triangle noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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