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Definition of "pentagon" [pen•ta•gon]

  • A polygon having five sides and five interior angles. (noun)
  • A five-sided building near Washington, D.C., containing the U.S. Department of Defense and the offices of the U.S. Armed Forces. Used with the. (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 "pentagon" in a sentence
  • "In particular, the fact that the pentagon is exempt from inclusion on U.S. emissions makes our participation in this conference a joke."
  • "He has majors, colonels and generals sending dispatches say that pulling out now would be a disaster while the pentagon is planning for a pull out for the 2006 elections."
  • "Notice the resulting shape appears to be a regular pentagon, that is, a pentagon with all angles congruent and all sides the same length."