Pentagon

['pentəɡ(ə)n] or ['pɛntəɡɑn]

(noun.) a government building with five sides that serves as the headquarters of the United States Department of Defense.

(noun.) the United States military establishment.

(noun.) a five-sided polygon.

Checker: Sinclair--From WordNet

(n.) A plane figure having five angles, and, consequently, five sides; any figure having five angles.

Checker: Ramona

n. (geom.) a plane figure having five angles and five sides: a fort with five bastions.—adj. Pentag′onal.—adv. Pentag′onally.

Inputed by Ethel