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polyatomic

American  
[pol-ee-uh-tom-ik] / ˌpɒl i əˈtɒm ɪk /

adjective

Chemistry.

  1. pertaining to a molecule containing more than two atoms.

polyatomic British  
/ ˌpɒlɪəˈtɒmɪk /

adjective

  1. (of a molecule) containing more than two atoms

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of polyatomic

First recorded in 1855–60; poly- + atomic

Vocabulary lists containing polyatomic

Chemistry - High School

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Chemical Reactions - Middle School

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Chemical Reactions - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Understanding how many atoms move and interact inside laser-driven polyatomic molecules is essential for any attempt to guide chemical reactions using intense light.

From Science Daily • Nov. 28, 2025

For example, electrons or polyatomic gases in a magnetic field do behave this way.

From Science Daily • Mar. 20, 2024

You can choose binary, polyatomic, and variable charge ionic compounds, as well as molecular compounds.

From Textbooks • Feb. 14, 2019

For example, potassium nitrate, KNO3, contains the K+ cation and the polyatomic anion.

From Textbooks • Feb. 14, 2019

In common with many other polyatomic open-chain alcohols, they generally possess a characteristic sweet, or mildly sweetish, taste.

From The Chemistry of Plant Life by Thatcher, Roscoe Wilfred

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.