Definition of triangle
1 : a polygon having three sides — compare spherical triangle
2a : 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 rodb : 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
3 : a situation in which one member of a couple is involved in a love affair with a third person
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Examples of triangle in a Sentence
She cut the sandwiches into triangles.
Illustration of triangle
Origin and Etymology 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 English Language Learners
triangle
playDefinition of triangle for English Language Learners
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: a shape that is made up of three lines and three angles
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: something that is shaped like a triangle
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: 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
TRIANGLE Defined for Kids
triangle
playDefinition of triangle for Students
1 : a flat geometric figure that has three sides and three angles
2 : something that has three sides and three angles a triangle of land
3 : a musical instrument made of a steel rod bent in the shape of a triangle with one open angle
Medical Dictionary
triangle
playMedical Definition of triangle
: a three-sided region or space and especially an anatomical one—see anterior triangle, carotid triangle, femoral triangle, posterior triangle, suboccipital triangle
Learn More about triangle
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See words that rhyme with triangle Spanish Central: Translation of triangle Nglish: Translation of triangle for Spanish speakers Britannica English: Translation of triangle for Arabic speakers Britannica.com: Encyclopedia article about triangle
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