ion

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

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 Japan built 11 Soryu-class submarines before moving on to a new class, Taigei, which uses lithium-ion batteries for greater cruising time underwater. Kyle Mizokami, Popular Mechanics, "Surfacing Japanese Submarine Collides With Commercial Ship," 9 Feb. 2021 Panasonic, which supplies lithium-ion cells to Tesla, showed off new batteries that are less than five percent cobalt. Gear Team, Wired, "The Best of CES 2021," 13 Jan. 2021 Meanwhile, the cost of lithium-ion batteries has dropped by 85%. John Fialka, Scientific American, "New Report Maps Out the U.S. Road to Net-Zero Emissions," 5 Feb. 2021 The space station is now equipped with 24 lithium-ion batteries to store power collected by the solar panels. Marcia Dunn, Chron, "Spacewalkers complete 4 years of power upgrades for station," 1 Feb. 2021 Right now, much of the supply chain is concentrated in China, which makes more than 70% of the world’s lithium-ion batteries, according to Benchmark. Rebecca Elliott, WSJ, "U.S. Mounts a Charge to Take On China, the King of Electric-Vehicle Batteries," 26 Jan. 2021 On clean energy, Biden has his work cut out for him: China has come to dominate manufacturing the materials needed for clean energy, including wind turbines, solar panels, and lithium-ion batteries needed for electric cars and battery storage. Josh Siegel, Washington Examiner, "Daily on Energy, sponsored by EFP: Biden playing catch-up on green manufacturing," 25 Jan. 2021 Mining the cobalt needed for lithium-ion batteries is ugly business. Gear Team, Wired, "The Best of CES 2021," 13 Jan. 2021 The guidelines also should include information on how to safely store vehicles with damaged lithium-ion batteries. Tom Krisher, Star Tribune, "NTSB says vehicle battery fires pose risks to 1st responders," 13 Jan. 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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Statistics for ion

Last Updated

25 Feb 2021

Cite this Entry

“Ion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ion. Accessed 5 Mar. 2021.

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More Definitions for ion

ion

noun

English Language Learners Definition of ion

 (Entry 1 of 2)

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

English Language Learners Definition of -ion (Entry 2 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

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)

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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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