英和和英

語源

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.

発音

• (米国発音, Canada) enPR: pĕn'təgän, IPA^(key): /ˈpɛn.tə.ɡɑn/
• (英国発音) enPR: pĕn'təgən, pĕn'təgŏn, IPA^(key): /ˈpɛn.tə.ɡən/, /ˈpɛn.tə.ɡɒn/
• ハイフネーション: pen‧ta‧gon

名詞

pentagon (複数形 pentagons)

1. (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, […]

2. A fort with five bastions.

派生語

• pentagonal

参考

• Wikipedia article on pentagons
• pentagram
• quinquangle

アナグラム

• pantogen