an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons
See also cation, anion
Word origin
C19: from Greek, literally: going, from ienai to go
-ion in British English
suffix forming nouns
indicating an action, process, or state
creation
objection
Compare -ation, -tion
Word origin
from Latin -iōn-, -io
ion in American English
(ˈaɪən; ˈaɪˌɑn)
noun
an electrically charged atom or group of atoms, the electrical charge of which results when a neutral atom or group of atoms loses or gains one or more electrons during chemical reactions, by the action of certain forms of radiant energy, etc.: the loss of electrons results in a positively charged ion (cation), the gain of electrons in a negatively charged ion (anion)
Word origin
arbitrary use (by Faraday) of Gr ion, neut. of iōn, prp. of ienai, to go < IE base *wei-, to go, chase after > L via, way
-ion in American English
(ən)
1.
the act or condition of
retrospection
2.
the result of
retroaction
Word origin
< Fr or L: Fr -ion < L -io, nom., (gen. -ionis)
ion in American English
(ˈaiən, ˈaiɑn)
noun Physics & Chemistry
1.
an electrically charged atom or group of atoms formed by the loss or gain of one ormore 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
Word origin
[‹ Gk ión going, neut. prp. of iénai to go; term introduced by Michael Faraday in 1834]
ion in Chemical Engineering
(aɪən)
Word forms: (regular plural) ions
noun
(Chemical Engineering: General)
An ion is a particle with a positive or negative charge, which is formed by the loss orgain of electrons (= particles with a negative charge) in an exchange reaction.
A cation is a positively charged ion that moves through the electrolyte toward the cathode under the influence of a potentialgradient.
Ions are always formed by removing electrons from an atom to form cations, or by addingelectrons to an atom to form anions.
An ion is a particle with a positive or negative charge, which is formed by the loss orgain of electrons in an exchange reaction.
ion exchange
Examples of 'ion' in a sentence
ion
Japanese companies are responsible for printed circuit boards and the lithium ion battery.
Times, Sunday Times (2007)
This is largely a matter of negative ions.
Chaitow, Leon The Beat Fatigue Workbook - how to identify the causes (1988)
It is powered by a lithium ion battery that lasts for up to an hour.
Times, Sunday Times (2009)
This is because it has more negative ions in it than normal.
Colette Harris, With Theresa Cheung PCOS DIET BOOK: How you can use the nutritional approach to deal with polycysticovary syndrome (2002)
There is not a negative ion in her body.
Times, Sunday Times (2012)
The air inside a vehicle is often highly polluted and low in negative ions.
Martlew, Gillian & Silver, Shelley Stay Well This Winter (1989)
Some have ion indicators to show when they are producing negative ions.
Turner, Roger Newman The Hayfever Handbook - a summer survival guide (1988)
Negative ions have a short lifespan and need to be manufactured constantly.
Martlew, Gillian & Silver, Shelley Stay Well This Winter (1989)
And the way you transform an atom into an ion is either by adding or taking away an electron.
Times, Sunday Times (2009)
They have shown the cause to be an imbalance of positive ions which leads to chemicals being released into the bloodstream.
Lamplugh, Diana & Sterwin, Diana & Nottidge, Pamela Survive the Nine to Five - a woman's guide to working well (1989)
They contain positively charged ions to balance out the negative static in your'do.
The Sun (2012)
It seems to fill the air with positive ions, like rain.
Times, Sunday Times (2008)
He suspected that the droplets might be collecting around ions, electrically charged atoms in the air.
Times, Sunday Times (2013)
The lithium ion battery is made up of 48 modules.
Times, Sunday Times (2011)
The pH of a solution is a measure of its hydrogen ion concentration and hence of its acidity.
Mayes, Adrienne The Dictionary of Nutritional Health (1986)
The tremendously high count of positive ions found in most modern offices is detrimental to health and well-being.
Lamplugh, Diana & Sterwin, Diana & Nottidge, Pamela Survive the Nine to Five - a woman's guide to working well (1989)
Silicon can suck in more lithium ions than carbon, and as a result push out more electrons.
Times, Sunday Times (2010)
This produces an avalanche of electrons and positive ions and the movement of the electrons and the ions produces an electric signal on the wire.
Times, Sunday Times (2010)
The electric motor can also be used for recharging the vehicle's lightweight lithium ion battery when you are braking.
The Sun (2008)
He said that his staff were still struggling to identify the precise cause, given that aircraft do not generally use lithium ion batteries.
Times, Sunday Times (2013)
Their action relies upon inhibiting the passage of calcium ions (electrically charged calcium atoms) into the smooth muscle walls.
Shreeve, Dr Caroline M Lower Your Blood Pressure in 4 Easy Stages (1989)
In human mitochondria, it takes ten hydrogen ions to crank the protein through a full circle and thus produce three molecules of ATP.
Oliver Morton Eating the Sun: How Plants Power the Planet (2007)
In other languages
ion
British English: ion NOUN
Ions are electrically charged atoms.
American English: ion
Brazilian Portuguese: íon
Chinese: 离子
European Spanish: ion
French: ion
German: Ion
Italian: ione
Japanese: イオン
Korean: 이온
European Portuguese: ião
Latin American Spanish: ion
All related terms of 'ion'
ion engine
a type of rocket engine in which thrust is obtained by the electrostatic acceleration of charged positive ions
ion rocket
a rocket propelled by an ion engine
oxonium ion
a positive ion produced from certain organic ethers or alcohols by adding a proton to the oxygen atom
ammonium ion
the ion NH 4 + , formed from ammonia and present in aqueous solutions of ammonia and in many salts
carbonium ion
type of positively charged organic ion
hydrogen ion
an ionized hydrogen atom , occurring in plasmas and in aqueous solutions of acids, in which it is solvated by one or more water molecules ; proton . Formula: H +
hydronium ion
positive ion , formed by the attachment of a proton to a water molecule : occurs in solutions of acids and behaves like a hydrogen ion
hydroxide ion
the negatively charged ion OH - of any base in a water solution
hydroxyl ion
→ hydroxide ion
ion exchange
the process in which ions are exchanged between a solution and an insoluble solid , usually a resin . It is used to soften water, to separate radioactive isotopes , and to purify certain industrial chemicals
positive ion
Physics & Chemistry See under ion (sense 1 )
hydroxonium ion
a positive ion , H 3 O + , formed by the attachment of a proton to a water molecule : occurs in solutions of acids and behaves like a hydrogen ion
ion propulsion
a type of propulsion for vehicles in outer space, the exhaust consisting of positive ions and negative electrons repelled from the vehicle by electrostatic forces, resulting in a very high exhaust velocity
sulphonium ion
a positive ion produced by the addition of a proton to the sulphur atom of a thiol or thio-ether
ion implantation
a technique used in the manufacture of semiconductor devices in which impurities are implanted by means of beams of electrically accelerated ions