poly·​atom·​ic ˌpä-lē-ə-ˈtä-mik How to pronounce polyatomic (audio)
: containing more than one and especially more than two atoms
polyatomic molecules

Word History


earlier, in sense "polyvalent," borrowed from French polyatomique, from poly- poly- + atomique atomic

First Known Use

1857, in the meaning defined above

Time Traveler
The first known use of polyatomic was in 1857

Dictionary Entries Near polyatomic

Cite this Entry

“Polyatomic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polyatomic. Accessed 30 May. 2024.

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