no·​na·​gon | \ ˈnō-nə-ˌgän How to pronounce nonagon (audio) \

Definition of nonagon

: a polygon of nine angles and nine sides

Examples of nonagon in a Sentence

Recent Examples on the Web The cylindrical core is a dull metallic silver with several irregular nonagon fuel assemblies arranged in its center. Daniel Oberhaus, Wired, "Coming Soon: A Nuclear Reactor—With a 3D Printed Core," 15 May 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nonagon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of nonagon

circa 1639, in the meaning defined above

History and Etymology for nonagon

Latin nonus ninth + English -gon — more at noon

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Time Traveler for nonagon

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The first known use of nonagon was circa 1639

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Cite this Entry

“Nonagon.” Dictionary, Merriam-Webster, Accessed 22 Oct. 2020.

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