Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

pentagon

play
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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of pentagon

  1. :  a polygon of five angles and five sides

Examples of pentagon in a sentence

  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 and Etymology 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 and Etymology 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 for Students

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





Seen and Heard

What made you want to look up pentagon? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

to criticize in a loud and angry way

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

confounded-person

Which is a synonym of indolent?

lazy frenetic melancholy philistine
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ