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
: a polygon of five angles and five sides
Examples of pentagon in a sentence
The general attended a meeting at the Pentagon.
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
Definition of Pentagon
: 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
Definition of pentagon for Students
: a flat geometric figure having five angles and five sides
Seen and Heard
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