triangle
Other forms: triangles
A triangle is a flat shape with three sides and three angles, like a slice of pizza, a yield sign, or the Greek letter delta. If you look carefully, you'll notice triangles all around you!
A triangle is a polygon, which is a closed shape like a square or a hexagon, but a triangle has only three sides. Wedges of pie and some tortilla chips are shaped like triangles. If you invite your crush to a movie and they bring a date, you have yourself a love triangle. Triangle comes from the Latin word triangulus, "three-cornered" or "having three angles," from the roots tri-, "three," and angulus, "angle or corner."
Definitions of triangle
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a three-sided polygon
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synonyms:
trigon, trilateral
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types:
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acute triangle, acute-angled triangle
a triangle whose interior angles are all acute
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equiangular triangle, equilateral triangle
a three-sided regular polygon
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isosceles triangle
a triangle with two equal sides
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oblique triangle
a triangle that contains no right angle
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obtuse triangle, obtuse-angled triangle
a triangle that contains an obtuse interior angle
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right triangle, right-angled triangle
a triangle with one right angle
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scalene triangle
a triangle with no two sides of equal length
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cuneus, wedge, wedge shape
any shape that is triangular in cross section
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delta
an object shaped like an equilateral triangle
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type of:
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polygon, polygonal shape
a closed plane figure bounded by straight sides
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something approximating the shape of a triangle
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any of various triangular drafting instruments used to draw straight lines at specified angles
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type of:
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drafting instrument
an instrument used by a draftsman in making drawings
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drafting instrument
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a percussion instrument consisting of a metal bar bent in the shape of an open triangle
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type of:
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percussion instrument, percussive instrument
a musical instrument in which the sound is produced by one object striking another
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percussion instrument, percussive instrument
Pronunciation
US
/ˌtraɪˈæŋgəl/
UK
/ˈtraɪæŋgəl/
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DISCLAIMER: These example sentences appear in various news sources and books to reflect the usage of the word ‘triangle'.
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