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ion

[ahy-uh n, ahy-on]
noun Physics, Chemistry.
  1. 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=.
  2. 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

Ion

[ahy-on]
noun
  1. 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.
  2. (italics) a drama on this subject (415? b.c.) by Euripides.
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-ion

  1. 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).
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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-

Ion.

  1. Ionic.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for ion

Contemporary Examples of ion

Historical Examples of ion

  • The ion differs from the molecule, the corpuscle and the atom in that it is an ion.

  • Ion replies that he is a foreigner, and the Athenians and Spartans will not appoint a foreigner to be their general.

    Ion

    Plato

  • ION: Yes, that is the sort of thing which the rhapsode will be sure to know.

    Ion

    Plato

  • And you, Ion, when the name of Homer is mentioned have plenty to say, and have nothing to say of others.

    Ion

    Plato

  • Now, Ion, will the charioteer or the physician be the better judge of the propriety of these lines?

    Ion

    Plato


British Dictionary definitions for ion

ion

noun
  1. an electrically charged atom or group of atoms formed by the loss or gain of one or more electronsSee also cation, anion
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Word Origin for ion

C19: from Greek, literally: going, from ienai to go

-ion

suffix forming nouns
  1. indicating an action, process, or statecreation; objection Compare -ation, -tion
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Word Origin for -ion

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

Word Origin and History for ion

n.

1834, introduced by English physicist and chemist Michael Faraday (suggested by the Rev. William Whewell, English polymath), coined from Greek ion, neuter present participle of ienai "go," from PIE root *ei- "to go, to walk" (cf. Greek eimi "I go;" Latin ire "to go," iter "a way;" Old Irish ethaim "I go;" Irish bothar "a road" (from *bou-itro- "cows' way"), Gaulish eimu "we go," Gothic iddja "went," Sanskrit e'ti "goes," imas "we go," ayanam "a going, way;" Avestan ae'iti "goes;" Old Persian aitiy "goes;" Lithuanian eiti "to go;" Old Church Slavonic iti "go;" Bulgarian ida "I go;" Russian idti "to go"). So called because ions move toward the electrode of opposite charge.

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-ion

suffix forming nouns of state, condition, or action from verbs, from Latin -ionem (nominative -io), sometimes via French -ion.

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Online Etymology Dictionary, © 2010 Douglas Harper

ion in Medicine

ion

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

ion in Science

ion

ən, īŏn′]
  1. 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.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

ion in Culture

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.

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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.