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ionize

verb

ion·​ize ˈī-ə-ˌnīz How to pronounce ionize (audio)
ionized; ionizing

transitive verb

: to convert wholly or partly into ions
ionizable adjective
ionizer noun

Examples of ionize in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The role of melanin The ionizing radiation, typically a destroyer of DNA and cells, appeared to be a nutrient for these resilient fungi. Mrigakshi Dixit, Interesting Engineering, 1 Dec. 2025 This study presents the first characterization of a domestic species in Chernobyl, establishing their importance for genetic studies into the effects of exposure to long-term, low-dose ionizing radiation. New Atlas, 27 Nov. 2025 The red in the image indicates ionized hydrogen, and blue shows ionized oxygen. Keith Cooper, Space.com, 26 Nov. 2025 The drug delivers targeted ionizing radiation directly to tumor cells, with the goal of minimizing damage to healthy cells, Novartis told Fox News Digital. Melissa Rudy, FOXNews.com, 4 Nov. 2025 See All Example Sentences for ionize

Word History

Etymology

ion + -ize, after German ionisiren (now ionisieren) or French ioniser

First Known Use

1898, in the meaning defined at transitive sense

Time Traveler
The first known use of ionize was in 1898

Cite this Entry

“Ionize.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ionize. Accessed 7 Dec. 2025.

Kids Definition

ionize

verb
ion·​ize ˈī-ə-ˌnīz How to pronounce ionize (audio)
ionized; ionizing
1
: to convert wholly or partly into ions
2
: to become ionized
ionizable adjective
ionization noun
ionizer noun

Medical Definition

ionize

verb
ion·​ize
variants or chiefly British ionise
ionized or chiefly British ionised; ionizing or chiefly British ionising

transitive verb

: to convert wholly or partly into ions
ionizable adjective
or chiefly British ionisable
ionization noun
or chiefly British ionisation

More from Merriam-Webster on ionize

Last Updated: - Updated example sentences
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