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anion Line breaks: anion
Pronunciation: /ˈanʌɪən/

Definition of anion in English:


A negatively charged ion, i.e. one that would be attracted to the anode in electrolysis. The opposite of cation.
Example sentences
  • When two atoms swap electrons to produce a cation and an anion, the two ions are attracted to each other.
  • During electrolysis an anion is attracted to the anode (positive electrode).
  • In an ionic compound there are two different types of ions present, the positively charged cations and the negatively charged anions.


Example sentences
  • An example of an anionic emulsifier is stearic acid.
  • The development of both cationic and anionic exchange materials did not occur until 1935.
  • The anionic lipids promote faster adsorption whether present in the bilayer vesicles or in the surface monolayer.


Mid 19th century: from anode or ana-, + ion.

Definition of anion in:
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