pentagon

From Middle French pentagone, from Late Latin pentagōnum, from Ancient Greek πεντάγωνον (pentágōnon), noun use of the neuter of the adjective πεντάγωνος (pentágōnos, “five-angled”), from πέντε (pénte, “five”) + -γωνος (-gōnos, “angled”). Equivalent to penta- +‎ -gon.

• (US, Canada) enPR: pĕn'təgän, IPA^(key): /ˈpɛn.təˌɡɑn/
• (UK) enPR: pĕn'təgən, pĕn'təgŏn, IPA^(key): /ˈpɛn.tə.ɡən/, /ˈpɛn.tə.ɡɒn/
• Hyphenation: pen‧ta‧gon

• Audio (Canada):

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pentagon (plural pentagons)

2. (geometry) A polygon with five sides and five angles.
   • 1884, A Square [pseudonym; Edwin A. Abbott], Flatland […] , London: Seeley & Co., Part I: This World, § 1.— Of the Nature of Flatland, page 3:

     Imagine a vast sheet of paper on which straight Lines, Triangles, Squares, Pentagons, Hexagons, and other figures, instead of remaining fixed in their places, move freely about, […]

3. (military) A fort with five bastions.

• 5-gon
• (geometry): quinquangle

• pentagonal

• pentagon on Wikipedia.Wikipedia
• pentagram
• quinquangle

• pantogen

pentagon c (singular definite pentagonen, plural indefinite pentagoner)

1. pentagon

• femkant

• pentagonal

• “pentagon” in Den Danske Ordbog

pentagon m (plural pentagons)

1. pentagon

From penta- +‎ -gon.

pentagon m (definite singular pentagonen, indefinite plural pentagoner, definite plural pentagonene)

1. (geometry) a pentagon

• femkant

• “pentagon” in The Bokmål Dictionary.
• “pentagon” in Det Norske Akademis ordbok (NAOB).

From penta- +‎ -gon.

pentagon m (definite singular pentagonen, indefinite plural pentagonar, definite plural pentagonane)

1. (geometry) a pentagon

• femkant

• “pentagon” in The Nynorsk Dictionary.

Borrowed from French pentagone, from Latin pentagonus.

pentagon n (plural pentagoane)

1. Pentagon

• “pentagon”, in DEX online—Dicționare ale limbii române (Dictionaries of the Romanian language) (in Romanian), 2004–2025