pho·​to·​ion·​i·​za·​tion ˌfō-tō-ˌī-ə-nə-ˈzā-shən How to pronounce photoionization (audio)
: ionization (as in the ionosphere) of a molecule or atom caused by absorption of radiant energy
photoionize transitive verb

Example Sentences

Recent Examples on the Web The breathing zone will be monitored with a photoionization detector to screen for volatile organic compounds (in the work zone). al, 14 Jan. 2020

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

Word History

First Known Use

1914, in the meaning defined above

Time Traveler
The first known use of photoionization was in 1914

Dictionary Entries Near photoionization

Cite this Entry

“Photoionization.” Dictionary, Merriam-Webster, Accessed 29 Mar. 2023.

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