a flat shape with three straight sides and three angles; a thing in the shape of a triangle 三角形；三角形物体 
Extra ExamplesTopics Colours and Shapesb2Use your protractor to construct an equilateral triangle. 用量角器作一个等边三角形。 a large region resembling an inverted triangle 近似一个倒三角形的大区域
Oxford Collocations Dictionaryadjective- equilateral
- isosceles
- right
- …
- construct
- draw
- form
- …
- the apex of a triangle
a simple musical instrument that consists of a long piece of metal bent into the shape of a triangle, that you hit with another piece of metal 三角铁（打击乐器） a situation involving three people in a complicated relationship 三角关系 the romantic triangle at the centre of the novel 小说中心的浪漫三角
- (North American English) (British English set square)
an instrument for drawing straight lines and angles, made from a flat piece of plastic or metal in the shape of a triangle with one angle of 90° 三角板；三角尺
Word Originlate Middle English: from Old French triangle or Latin triangulum, neuter of triangulus ‘three-cornered’ (see tri- and the noun angle).