ion

noun
\ ˈī-ən How to pronounce ion (audio) , ˈī-ˌän How to pronounce ion (audio) \

Definition of ion

 (Entry 1 of 3)

1 : an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons
2 : a charged subatomic particle (such as a free electron)

Definition of Ion (Entry 2 of 3)

Ionic

Definition of -ion (Entry 3 of 3)

1a : act or process validation
b : result of an act or process regulation
2 : state or condition hydration

Examples of ion in a Sentence

Recent Examples on the Web: Noun The prize for chemistry was given to three scientists — John B. Goodenough, M. Stanley Whittingham and Akira Yoshino — who developed lithium-ion batteries, the energy storage systems that have revolutionized portable electronics. New York Times, 7 Oct. 2021 The Nobel Prize winners who developed lithium-ion batteries were funded by the National Science Foundation and the Energy Department. Paul M. Dabbar, WSJ, 5 Oct. 2021 The hybrid combines a 2.5L four-cylinder engine, lithium-ion batteries and a continuously variable transmission. Mark Phelan, Detroit Free Press, 5 Oct. 2021 Lithium-ion batteries first appeared in electric vehicles around 2012, while an electric vehicle’s life is about 12 years, Spangenberger said. Debra Utacia Krol, The Arizona Republic, 2 Oct. 2021 So the race is on to find alternatives that use less or no cobalt, or that use hydrogen fuel cells instead of lithium-ion batteries. David Meyer, Fortune, 29 Sep. 2021 As a joint venture with Ford’s South Korean partner, SK Innovation, the plants will produce advanced lithium-ion batteries from 2025 to power future Fords and Lincoln EV models. Peter Lyon, Forbes, 28 Sep. 2021 China, on the other hand, is the world’s biggest importer of cobalt, which its companies use to make lithium-ion batteries for electric vehicles, smartphones, tablets, laptops, and high-value items. Carlos Mureithi, Quartz, 15 Sep. 2021 The alliance with Ford is a significant validation of Straubel’s vision for Redwood to become a virtual mining powerhouse, recovering highly valuable and reusable materials from battery scraps and used lithium-ion cells. Alan Ohnsman, Forbes, 22 Sep. 2021

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

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First Known Use of ion

Noun

circa 1834, in the meaning defined at sense 1

History and Etymology for ion

Noun

Greek, neuter of iōn, present participle of ienai to go — more at issue entry 1

Noun suffix

French -ion, from Latin -ion-, -io

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Dictionary Entries Near ion

-ion

ion

Iona

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Statistics for ion

Last Updated

11 Oct 2021

Cite this Entry

“Ion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ion. Accessed 17 Oct. 2021.

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More Definitions for ion

ion

noun

English Language Learners Definition of ion

 (Entry 1 of 2)

: an atom or group of atoms that has a positive or negative electric charge from losing or gaining one or more electrons

-ion

noun suffix

English Language Learners Definition of -ion (Entry 3 of 2)

: act or process
: result of an act or process
: state or condition

ion

noun
\ ˈī-ən How to pronounce ion (audio) , ˈī-ˌän \

Kids Definition of ion

: an atom or group of atoms that carries an electric charge

-ion

noun suffix

Kids Definition of -ion

1 : act or process construction
2 : result of an act or process regulation eruption
3 : state or condition perfection

ion

noun
\ ˈī-ən How to pronounce ion (audio) , ˈī-ˌän How to pronounce ion (audio) \

Medical Definition of ion

1 : an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons — see anion, cation
2 : a charged subatomic particle (as a free electron)

More from Merriam-Webster on ion

Nglish: Translation of ion for Spanish Speakers

Britannica English: Translation of ion for Arabic Speakers

Britannica.com: Encyclopedia article about ion

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