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

Definition of ionize

transitive verb

: to convert wholly or partly into ions

Other Words from ionize

ionizable \ ˈī-​ə-​ˌnī-​zə-​bəl How to pronounce ionize (audio) \ adjective
ionizer \ ˈī-​ə-​ˌnī-​zər How to pronounce ionize (audio) \ noun

Examples of ionize in a Sentence

Recent Examples on the Web Cosmic rays influence pressure and temperature, drive galactic winds, and ionize molecules in star-fertile regions like supernova remnants. WIRED, 28 Aug. 2022 These would absorb any light at or above a wavelength that was sufficient to ionize the hydrogen, essentially making the Universe opaque to these wavelengths. John Timmer, Ars Technica, 22 July 2022 The solar radiation may ionize some of the molecules in the comet's coma, resulting in energetic electrons colliding with other molecules and releasing heat, Science Alert reports. Elizabeth Gamillo, Smithsonian Magazine, 8 July 2021 The ensuing energetic radiation and stellar winds ionize and blow off surrounding material. Ethan Siegel, Forbes, 28 June 2021 After exposure to sunlight, the vapor clouds ionize and take on a violet color. Sarah Brookbank, The Enquirer, 7 May 2021 After exposure to sunlight and 30 seconds have passed, the clouds will ionize and turn a violet hue, generating a magnetic field perturbation. Julia Musto, Fox News, 7 May 2021 This radiation is energetic enough to ionize them, enabling that portion of the Universe to be transparent. Ethan Siegel, Forbes, 15 Apr. 2021 Ion drives use electricity to ionize propellants, which knocks electrons free from the gas. Daniel Oberhaus, Wired, 15 Oct. 2020 See More

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

First Known Use of ionize

1898, in the meaning defined at transitive sense

History and Etymology for ionize

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

Learn More About ionize

Dictionary Entries Near ionize

ionization potential



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Statistics for ionize

Last Updated

2 Sep 2022

Cite this Entry

“Ionize.” Dictionary, Merriam-Webster, Accessed 5 Oct. 2022.

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More Definitions for ionize


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

Kids Definition of ionize

: to change into ions


variants: or chiefly British ionise \ ˈī-​ə-​ˌnīz How to pronounce ionize (audio) \
ionized or chiefly British ionised; ionizing or chiefly British ionising

Medical Definition of ionize

transitive verb

: to convert wholly or partly into ions

Other Words from ionize

ionizable or chiefly British ionisable \ -​ˌnī-​zə-​bəl How to pronounce ionize (audio) \ adjective
ionization or chiefly British ionisation \ ˌī-​ə-​nə-​ˈzā-​shən How to pronounce ionize (audio) \ noun

More from Merriam-Webster on ionize

Nglish: Translation of ionize for Spanish Speakers

Britannica English: Translation of ionize for Arabic Speakers


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