noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

: a shape that is made up of three lines and three angles

: 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

Full Definition of TRIANGLE

:  a polygon having three sides — compare spherical triangle
a :  a percussion instrument consisting of a rod of steel bent into the form of a triangle open at one angle and sounded by striking with a small metal rod
b :  a drafting instrument consisting of a thin flat right-angled triangle of wood or plastic with acute angles of 45 degrees or of 30 degrees and 60 degrees
:  a situation in which one member of a couple is involved in a love affair with a third person

Examples of TRIANGLE

  1. She cut the sandwiches into triangles.

Illustration of TRIANGLE

Origin of TRIANGLE

Middle English, from Anglo-French, from Latin triangulum, from neuter of triangulus triangular, from tri- + angulus angle
First Known Use: 14th century
TRIANGLE Defined for Kids


noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

Definition of TRIANGLE for Kids

:  a flat geometric figure that has three sides and three angles
:  something that has three sides and three angles <a triangle of land>
:  a musical instrument made of a steel rod bent in the shape of a triangle with one open angle
Medical Dictionary


noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

Medical Definition of TRIANGLE

:  a three-sided region or space and especially an anatomical one—see anterior triangle, posterior triangle, scarpa's triangle, suboccipital triangle, superior carotid triangle
July 04, 2015
stringent Hear it
rigorous, strict, or severe
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