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.
Nuclear power plants use ionizing radiation, which has been classified as carcinogenic by the International Agency for Research on Cancer. Krisztian Elcsics, Hartford Courant, 12 May 2026 These blackouts occur when intense X-ray and ultraviolet radiation from solar flares ionize Earth's upper atmosphere, interfering with high-frequency radio signals used by aviators, mariners and amateur radio operators. Daisy Dobrijevic, Space.com, 11 May 2026 Look for non-ionizing air purification; ionizing air filters can generate ozone, which worsens indoor air quality. Levi Keller, The Conversation, 5 May 2026 Studies have linked prolonged exposure to ionizing radiation from radioactive fallout to elevated risks of disease, most notably leukemia and thyroid cancer, particularly among children. Georgina Jedikovska, Interesting Engineering, 26 Apr. 2026 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 17 May. 2026.

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

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