anion

[an-ahy-uh n] /ˈænˌaɪ ən/
noun, Physical Chemistry
1.
a negatively charged ion, as one attracted to the anode in electrolysis.
2.
any negatively charged atom or group of atoms (opposed to cation).
Origin
1825-35; < Greek, neuter of aniṓn going up (present participle of aniénai to go up), equivalent to an- an-3 + -i- go + -ōn present participle suffix
Related forms
anionic
[an-ahy-on-ik] /ˌæn aɪˈɒn ɪk/ (Show IPA), adjective
anionically, adverb
British Dictionary definitions for anion

anion

/ˈænˌaɪən/
noun
1.
a negatively charged ion; an ion that is attracted to the anode during electrolysis Compare cation
Derived Forms
anionic (ˌænaɪˈɒnɪk) adjective
Word Origin
C19: from ana- + ion
Word Origin and History for anion
n.

"a negatively charged ion, which moves toward the anode (q.v.) during electrolysis," 1834, proposed by the Rev. William Whewell (1794-1866), English polymath, and published by English physicist Michael Faraday, from Greek anion "(thing) going up," neuter past participle of anienai "go up," from ana "up" (see ana-) + ienai "go" (see ion).

anion in Medicine

anion an·i·on (ān'ī'ən)
n.
A negatively charged ion, especially one that migrates to the anode in electrolysis.

anion in Science
anion
  (ān'ī'ən)   
An ion with net negative charge, having more electrons than protons. In electrolysis, anions migrate to a positively charged anode. Compare cation.