pentagon

American  

[pen-tuh-gon, -guhn] / ˈpɛn təˌgɒn, -gən /

noun

1. a polygon having five angles and five sides.

2. the Pentagon,

   1. a building in Arlington, Virginia, having a plan in the form of a regular pentagon, containing most U.S. Defense Department offices.

   2. the U.S. Department of Defense; the U.S. military establishment.

---

Pentagon ¹ British  

/ ˈpɛntəˌɡɒn /

noun

1. the five-sided building in Arlington, Virginia, that houses the headquarters of the US Department of Defense

2. the military leadership of the US

---

pentagon ² British  

/ ˈpɛntəˌɡɒn, pɛnˈtæɡənəl /

noun

1. a polygon having five sides

---

pentagon Scientific  

/ pĕn′tə-gŏn′ /

1. A polygon having five sides.

---

Pentagon ¹ Cultural  

1. An immense five-sided building in Virginia, just outside Washington, D.C., that serves as headquarters for the Department of Defense.

---

pentagon ² Cultural  

1. A polygon having five sides.

---

Discover More

The term is often used to refer to the Department of Defense or the military: “The Pentagon agreed today to submit the modified weapons plan to the president.”

The Pentagon was severely damaged by the September 11 attacks.

The Pentagon is a huge five-sided building near Washington, D.C., that contains offices of the Department of Defense.

Other Word Forms

• pentagonal adjective
• pentagonally adverb
• subpentagonal adjective

Etymology

Origin of pentagon

1560–70; < Late Latin pentagōnum < Greek pentágōnon, noun use of neuter of pentágōnos five-angled. See penta-, -gon

Example Sentences

It's like jumping into a kaleidoscope, with constantly shifting triangles, pentagons and octagons.

From BBC

This process starts with the assembly of small, triangular parts into hexagons, which subsequently join up with pentagons to form the icosahedral structures of viral capsids.

From Science Daily

The vision involves developing human capital, the digital economy and inclusivity and sustainability, he said, referring to it as the "pentagon strategy".

From Reuters

They could arrange four hat tiles into a hexagonlike structure, two tiles into a pentagon and another combination of two tiles into a parallelogram.

From Scientific American

Karen Viglione Lauterwasser despairs over errors “like calling the divisions in a hockey game quarters or having a pentagon shaped table with six chairs.”

From Washington Post