mon·​atom·​ic | \ ˌmä-nə-ˈtä-mik How to pronounce monatomic (audio) \

Definition of monatomic

: consisting of one atom especially : having but one atom in the molecule

Examples of monatomic in a Sentence

Recent Examples on the Web In particular, both diatomic hydrogen and monatomic helium can permeate the seals. Peter Bright, Ars Technica, "Helium implicated in weird iPhone malfunctions," 31 Oct. 2018

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

First Known Use of monatomic

1848, in the meaning defined above

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The first known use of monatomic was in 1848

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Cite this Entry

“Monatomic.” Dictionary, Merriam-Webster, Accessed 1 Apr. 2020.

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More Definitions for monatomic


mon·​atom·​ic | \ ˌmän-ə-ˈtäm-ik How to pronounce monatomic (audio) \

Medical Definition of monatomic

1 : consisting of one atom especially : having but one atom in the molecule

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