pentagonal

adjective

pen·​tag·​o·​nal pen-ˈta-gə-nᵊl How to pronounce pentagonal (audio)
1
: having five sides and five angles
2
: having a pentagon as a cross section or as a base
a pentagonal pyramid
pentagonally adverb

Examples of pentagonal in a Sentence

Recent Examples on the Web The kitchen is quite small and has an odd, pentagonal shape which Ho kept. Kimberley Mok, Treehugger, 22 Aug. 2023 The daytime footage shows a housing complex composed of five large multi-story apartment buildings arranged in a pentagonal shape. Sébastien Roblin, Popular Mechanics, 5 July 2023 The enclosure of the latest Stradivari is a complex one—essentially a pentagonal shape when viewed from above—evolved from the elliptical footprint of the original, which launched in the early 2000s. Robert Ross, Robb Report, 28 May 2023 Marjorie Rice, a California housewife, found a new family of pentagonal tilings in 1975. Erica Klarreich, Quanta Magazine, 4 Apr. 2023 According to park rangers, the pentagonal fort could be equipped with more than 200 cannon, which could deter enemies with a ring of fire. Patricia Harris, BostonGlobe.com, 20 Apr. 2023 The stone, which looks to be set in platinum, is flanked by what appear to be two pentagonal-cut stones. Carrie Goldberg, Harper's BAZAAR, 23 July 2020 These are attracted to places where hexagonal arrangements of carbon atoms attach to pentagonal arrangements — intersections that appear all over fullerenes. James R. Riordon, Quanta Magazine, 20 Dec. 2022 When placed on a hot surface, about 200°C, one set of hinges folds and the robot curls into a pentagonal wheel. IEEE Spectrum, 23 Aug. 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'pentagonal.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1571, in the meaning defined at sense 1

Time Traveler
The first known use of pentagonal was in 1571

Dictionary Entries Near pentagonal

Cite this Entry

“Pentagonal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pentagonal. Accessed 25 May. 2024.

Kids Definition

pentagonal

adjective
pen·​tag·​o·​nal pen-ˈtag-ən-ᵊl How to pronounce pentagonal (audio)
1
: having five sides and five angles
2
: having a pentagon as a cross section or as a base
a pentagonal pyramid

More from Merriam-Webster on pentagonal

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