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Definition of "triangle" []

  • The plane figure formed by connecting three points not in a straight line by straight line segments; a three-sided polygon. (noun)
  • Something shaped like such a figure: a triangle of land. (noun)
  • Any of various flat, three-sided drawing and drafting guides, used especially to draw straight lines at specific angles. (noun)
  • Music A percussion instrument consisting of a piece of metal in the shape of a triangle open at one angle. (noun)
  • A relationship involving three people, especially a ménage à trois. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "triangle" in a sentence
  • "After a long series of experiments, guided by his ideas of the genesis of geometric figures, Séguin became aware that the triangle is the figure most easily drawn."
  • "The Moslems, I am told, cut three locks – a triangle is a favourite Moslem tattoo pattern."
  • "Because when I go out on head coaching interviews and if I mention the word 'triangle,' it makes general managers and owners cringe."