There are 2 main definitions of pentagon in English:

pentagon1

Line breaks: penta|gon
Pronunciation: /ˈpɛntəɡ(ə)n
 
/

noun

A 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.

Origin

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

Derivatives

pentagonal

Pronunciation: /-ˈtaɡ(ə)n(ə)l/
adjective
More example sentences
  • Ring compounds most often contain five or six atoms to form pentagonal or hexagonal structures.
  • This only occurs at the time when the pentagonal symmetry of the flower becomes visible and organ identity genes are expressed.
  • The Sergeant gave her a pentagonal shaped cabin slightly larger, slightly more comfortable than the one she had had downstairs, sporting retractable shelves which sprung out here and there to alter the shape of the room.

Definition of pentagon in: