Definition of pentagon in English:

pentagon

Syllabification: pen·ta·gon
Pronunciation: /ˈpen(t)əˌɡän
 
/

noun

1A plane figure with five straight sides and five angles.
More example sentences
  • In the second case, if the convex polygon is a pentagon incorporating all five points, then any four of these points can be connected to form a quadrilateral.
  • This says that the most stable arrangement is a pentagon surrounded by five hexagons.
  • The hexagons, pentagons, and triangles that make up the biomes all have their own unique specification due to the irregular nature of the site.
2 (the Pentagon) The pentagonal building serving as the headquarters of the US Department of Defense, near Washington, DC.
2.1The US Department of Defense: the Pentagon said 19 of its soldiers had been killed

Origin

late 16th century: via Latin from Greek pentagōnon, neuter (used as a noun) of pentagōnos 'five-angled'.

Derivatives

pentagonal

Pronunciation: /penˈtaɡənəl/
adjective
More example sentences
  • Here are two pictures of the pentagonal coffee table that I mentioned in the book.
  • I managed to fit all the yellow nets for the pentagonal prism, pentagonal antiprism, and pentagrammic prism all on one page.

Definition of pentagon in: