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)

Ion

2 of 3

abbreviation

Ionic

-ion

3 of 3

noun suffix

1
a
: 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
Another problem for firefighters is that lithium ion battery fires are harder to extinguish than a regular fire, Hunter said. Jamie L. Lareau, Detroit Free Press, 1 Mar. 2024 This structural diversity reduces the likelihood of ion trapping and improves overall conductivity. IEEE Spectrum, 15 Feb. 2024 This solution contains silver ions that kill bacteria and prevent cavities. Melissa Willets, Parents, 9 Mar. 2024 My group is also investigating new types of batteries beyond lithium ion. Wesley Chang, CBS News, 5 Mar. 2024 Specifically, solid electrolytes are typically worse at conducting lithium ions through their material. IEEE Spectrum, 15 Feb. 2024 Whereas older stars like our sun blast atoms, ions and molecules into space, HH 211 ejects mostly molecular matter. Lori Youmshajekian, Scientific American, 14 Dec. 2023 This Edge also used a lithium ion battery that was meant to provide about 50 miles of driving range and a fuel cell as a range extender. Sam Abuelsamid, Forbes, 27 Feb. 2024 But these alternative compounds are more costly than simple rock salt and don’t reduce the negative environmental impact of chloride ions. Meghan Bartels, Scientific American, 16 Jan. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ion.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

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

Noun suffix

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

First Known Use

Noun

circa 1834, in the meaning defined at sense 1

Time Traveler
The first known use of ion was circa 1834

Dictionary Entries Near ion

Cite this Entry

“Ion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ion. Accessed 28 Mar. 2024.

Kids Definition

ion

1 of 2 noun
ˈī-ən How to pronounce ion (audio)
ˈī-ˌän
: 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

-ion

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

Noun suffix

derived from Latin -ion (suffix) "act or process"

Medical Definition

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

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