ion

1 of 3

noun

ˈī-ən  ˈī-ˌän 

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 workhorse in batteries is lithium ion which has done so much to support the changing face of the modern world, from cellphones to electric vehicles, drones to toys, personal computers to spacecraft. —Llewellyn King, Forbes.com, 1 Aug. 2025

Scientists need at least two spacecraft, each positioned in bespoke polar orbits and specially instrumented to measure magnetic fields, electric fields, electrons, and ions. —Stephen Clark, ArsTechnica, 24 July 2025

Each 15 μm × 15 μm analysis area was pre-sputtered for 2 min with a Cs+ ion beam current of 5 nA to remove the surface coating and potential contamination. —Keith Cooper, Space.com, 16 July 2025

This 1300-watt dryer uses negative ion HydraHeat tech to smooth frizz and boost shine without flattening your strands. —Christa Joanna Lee, Allure, 5 July 2025

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

Phrases Containing ion

• hydrogen ion
• ion channel
• ion engine
• ion exchange
• ion exchange resin
• lithium-ion battery

Rhymes for ion

• amphitryon
• dandelion
• hawaiian
• ixion
• orion
• procyon
• visayan
• heian
• lion
• mayan
• scion

Kids Definition

ion

1 of 2 noun

ˈī-ən 

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

ion

noun

ˈī-ən  ˈī-ˌän 

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)