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
The material has a specific crystal structure [that] enables very fast ion transport. Kat Friedrich, Ars Technica, 20 Sep. 2024 When overheated, lithium ion batteries can smoke, melt and even catch on fire. Jane Thier, Fortune, 17 Sep. 2024 According to the Associated Press: Electric vehicles with lithium ion batteries can catch fire if the batteries short circuit and start to heat up. Logan Carter / Jalopnik, Quartz, 1 Oct. 2024 Electric vehicles with lithium ion batteries can catch fire if the batteries short circuit and start to heat up. Sasha Rogelberg, Fortune, 27 Sep. 2024 See all Example Sentences for ion 

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 31 Oct. 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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