Oxford Advanced American Dictionary

Definition of pentagon noun from the Oxford Advanced Learner's Dictionary

pentagon

noun
pentagon pronunciation English ˈpentəɡən pentagon pronunciation American ˈpentəɡɑːn
 
1 [countable] (geometry) a flat shape with five straight sides and five angles2 the Pentagon [singular] the building near Washington DC that is the headquarters of the US Department of Defense and the military leadersa spokesman for the Pentagon