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ion

[ ahy-uhn, ahy-on ]
/ ˈaɪ ən, ˈaɪ ɒn /
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noun Physics, Chemistry.

an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation (positive ion ), which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion (negative ion ), which is created by an electron gain and is attracted to the anode. The valence of an ion is equal to the number of electrons lost or gained and is indicated by a plus sign for cations and a minus sign for anions, thus: Na+, Cl−, Ca++, S=.
one of the electrically charged particles formed in a gas by electric discharge or the like.

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Origin of ion

<Greek ión going, neuter present participle of iénai to go; term introduced by Michael Faraday in 1834

Definition for ion (2 of 4)

Ion
[ ahy-on ]
/ ˈaɪ ɒn /

noun

Classical Mythology. the eponymous ancestor of the Ionians: a son of Apollo and Creusa who is abandoned by his mother but returns to become an attendant in Apollo's temple at Delphi.
(italics) a drama on this subject (415? b.c.) by Euripides.

Definition for ion (3 of 4)

-ion

a suffix, appearing in words of Latin origin, denoting action or condition, used in Latin and in English to form nouns from stems of Latin adjectives (communion; union), verbs (legion; opinion), and especially past participles (allusion; creation; fusion; notion; torsion).
Compare -cion, -xion.

Origin of -ion

<Latin -iōn- (stem of -iō) suffix forming nouns, especially on past participle stems; replacing Middle English -ioun<Anglo-French <Latin -iōn-

Definition for ion (4 of 4)

Ion.

abbreviation

Ionic.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for ion (1 of 2)

ion
/ (ˈaɪən, -ɒn) /

noun

an electrically charged atom or group of atoms formed by the loss or gain of one or more electronsSee also cation, anion
C19: from Greek, literally: going, from ienai to go

British Dictionary definitions for ion (2 of 2)

-ion

suffix forming nouns

indicating an action, process, or statecreation; objection Compare -ation, -tion
from Latin -iōn-, -io
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for ion

ion
[ īən, īŏn′ ]

n.

An atom or a group of atoms that has acquired a net electric charge by gaining or losing one or more electrons.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for ion

ion
[ īən, īŏn′ ]

An atom or a group of atoms that has an electric charge. Positive ions, or cations, are formed by the loss of electrons; negative ions, or anions, are formed by the gain of electrons.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for ion

ion
[ (eye-uhn, eye-on) ]

An atom that has either lost or gained one or more electrons, so that it has an electrical charge. Ions can be either positively or negatively charged.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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