triangle /ˈtraɪˌæŋgəl/ noun
plural triangles
plural triangles
Learner's definition of TRIANGLE
: a shape that is made up of three lines and three angles see picture at geometry; see also equilateral triangle, isosceles triangle, right triangle
: something that is shaped like a triangle
: a musical instrument that is made of a steel rod bent into the shape of a triangle and that you play by hitting with a metal rod
: a situation in which one member of a couple is involved in a romantic or sexual relationship with another person
US : a usually plastic or metal device that is shaped like a triangle and used for drawing straight lines and angles
called also (British) set square