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pentagon

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noun pen·ta·gon \ˈpen-tə-ˌgän\

Simple Definition of pentagon

  • mathematics : a flat shape that has five sides and five corners

  • the Pentagon : the building in Washington, D.C., that is the headquarters of the U.S. Department of Defense

  • : the leaders of the U.S. military

Full Definition of pentagon

  1. :  a polygon of five angles and five sides

Examples of pentagon

  1. The general attended a meeting at the Pentagon.

  2. There was disagreement between the President and the Pentagon over the new military budget.



Origin of pentagon

Greek pentagōnon, from neuter of pentagōnos pentagonal, from penta- + gōnia angle — more at -gon


First Known Use: 1570

Rhymes with pentagon

Abadan, Acheron, Ahriman, aileron, alençon, amazon, Amazon, amnion, and so on, antiphon, Aragon, autobahn, balmacaan, Bantustan, baryon, Basilan, bear down on, beat up on, betatron, biathlon, cabochon, call upon, calutron, carillon, carry-on, carry on, celadon, check up on, chorion, colophon, come upon, Culiacán, cyclotron, decagon, decathlon, demijohn, dine out on, early on, echelon, electron, elevon, enteron, epsilon, ethephon, etymon, fall back on, fermion, follow-on, Genghis Khan, get it on, go back on, going on, goings-on, gonfalon, Grand Teton, graviton, hanger-on, harijan, helicon, heptagon, hereupon, hexagon, hold out on, hopping John, Huascarán, hyperon, Isfahan, isochron, Kublai Khan, Kyrgyzstan, lay eyes on, Lebanon, leprechaun, liaison, Lipizzan, load up on, logion, looker-on, macédoine, marathon, Marathon, marzipan, mastodon, Mazatlán, Miquelon, miss out on, morion, move in on, myrmidon, nonagon, noumenon, nucleon, Oberon, octagon, off and on, omicron, Oregon, organon, ostracon, Pakistan, Palawan, pantheon, paragon, Parmesan, parmigiana, Parthenon, peloton, pentathlon, Percheron, Phlegethon, Phocion, pick up on, polygon, positron, Procyon, put-upon, Rajasthan, Ramadan, ride herd on, run low on, run out on, run upon, set eyes on, set foot on, set upon, silicon, sneak up on, Süleyman, tachyon, Taiyuan, talkathon, telamon, telethon, thereupon, tie one on, triathlon, Tucumán, upsilon, virion, walkathon, walk out on, whereupon, woebegone, work upon, Yerevan, Xiangtan, Zahedan


Pentagon

noun pen·ta·gon

Definition of Pentagon

  1. :  the United States military leadership



Origin of pentagon

the Pentagon building, headquarters of the Department of Defense


First Known Use: 1945



PENTAGON Defined for Kids

pentagon

play
noun pen·ta·gon \ˈpen-tə-ˌgän\

Definition of pentagon

  1. :  a flat geometric figure having five angles and five sides





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