ion

[ahy-uh n, ahy-on] /ˈaɪ ən, ˈaɪ ɒn/

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.

Origin

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

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.

Examples from the web for ions

The ionosphere is named for the ions created within this layer by energetic particles from sunlight and outer space.
Acids react with carbonate ions, in effect tying them up.
The smashup also creates charged atoms, or ions, that are detectable.
Hydrogen peroxide reduces other chemicals into iodide ions.
It is plasma--an electrically charged, high-energy soup of ions and electrons.
Up till this point, nestled in between casein molecules have been calcium ions, which help hold the proteins together.
These charged atoms or molecules are known as ions, and the amount of charge on an ion is known as its oxidation state.
These quantum particles could be ions, atoms, or subatomic particles.
When the protein sees the light, it opens up and allows ions to enter the neuron, making it fire.
When light hits the transplanted proteins, they allow ions to stream into the neurons, which makes them fire.

British Dictionary definitions for ions

ion

/ˈaɪən; -ɒn/

noun

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

Word Origin and History for ions

ion

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.

ions in Medicine

ion i·on (ī'ən, ī'ŏn')
n.
An atom or a group of atoms that has acquired a net electric charge by gaining or losing one or more electrons.

ions in Science

ion

(ī'ən, ī'ŏn')
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.

ions 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.

Related Abbreviations for ions

ION

Institute of Nutrition