ion

noun \ ˈī-ən , ˈī-ˌän \
Updated on: 8 Nov 2017

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
2 :a charged subatomic particle (such as a free electron)

Recent Examples of ion from the Web

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.

Origin and Etymology of ion

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

Other Chemical Engineering Terms


Ion

abbreviation

Definition of Ion

Ionic

-ion

noun suffix

Definition of -ion

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

Origin and Etymology of -ion

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


ION Defined for English Language Learners

ion

noun

Definition of ion for English Language Learners

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


-ion

noun suffix

Definition of -ion for English Language Learners

  • : act or process

  • : result of an act or process

  • : state or condition


ION Defined for Kids

ion

noun \ ˈī-ən , ˈī-ˌän \

Definition of ion for Students

:an atom or group of atoms that carries an electric charge

-ion

noun suffix

Definition of -ion for Students

1 :act or process
  • construction
2 :result of an act or process
  • regulation
  • eruption
3 :state or condition
  • perfection

Medical Dictionary

ion

noun \ ˈī-ən , ˈī-ˌän \

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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