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 The Fairfield projects would be developed in separate phases, each coming with enough lithium-ion batteries to store half the farm’s electrical generation for a few hours. Brian Maffly, The Salt Lake Tribune, "Big solar farms could dominate the future of a Utah hamlet trying to preserve its small-town feel," 19 Oct. 2020 The lithium-ion batteries in electric cars are similar to those found in consumer electronics, which store large amounts of energy relative to their size. Ben Foldy, WSJ, "Auto Makers Grapple With Battery-Fire Risks in Electric Vehicles," 19 Oct. 2020 Solid-state batteries can charge quicker and have a larger storage capacity than the lithium-ion batteries found in current vehicles. Roberto Baldwin, Car and Driver, "iPhone Builder Foxconn Is Making an EV Platform with a Solid-State Battery," 16 Oct. 2020 Although many grid operators are now installing large arrays of lithium-ion batteries for this type of storage, batteries can typically only store 4 to 6 hours’ worth of electricity. Brad Plumer, New York Times, "Environmentalists and Dam Operators, at War for Years, Start Making Peace," 13 Oct. 2020 The anode in modern lithium-ion batteries is graphite. Scott K. Johnson, Ars Technica, "Here’s what Tesla will put in its new batteries," 24 Sep. 2020 The 2019 prize was awarded to three scientists for their work developing lithium-ion batteries—power sources that touched off a technological revolution and gave rise to cellphones and electric cars. Brianna Abbott, WSJ, "Nobel Prize in Chemistry Is Awarded for Crispr Gene-Editing Technology," 7 Oct. 2020 Ampd sells and leases the Enertainers, which are filled with enough lithium-ion, nickel, cobalt and manganese batteries to power 25,000 iPhones. Dan Murtaugh, Bloomberg.com, "Battery Revolution Prepares to Take on Noisy Construction Sites," 22 Sep. 2020 China now produces over two-thirds of the world’s solar photovoltaic panels and lithium-ion batteries, and 45% of all wind turbines. Gernot Wagner, Bloomberg.com, "China’s Carbon Neutrality Goal is Good Policy and Good Politics," 25 Sep. 2020

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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Time Traveler for ion

Time Traveler

The first known use of ion was circa 1834

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Statistics for ion

Last Updated

22 Oct 2020

Cite this Entry

“Ion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ion. Accessed 26 Oct. 2020.

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More Definitions for ion

ion

noun
How to pronounce -ion (audio)

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

Comments on ion

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