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cation Line breaks: cat¦ion
Pronunciation: /ˈkatʌɪən/

Definition of cation in English:


A positively charged ion, i.e. one that would be attracted to the cathode in electrolysis. The opposite of anion.
Example sentences
  • When two atoms swap electrons to produce a cation and an anion, the two ions are attracted to each other.
  • The key step in a unimolecular reaction is the formation of the carbon cation, or carbonium ion, by the departure of the leaving group.
  • The functional groups of iron hydroxides may sequestrate some cations and anions.


Pronunciation: /katʌɪˈɒnɪk/
Example sentences
  • The primary conditioning ingredients are cationic surfactants, silicones, and polymers.
  • More than a decade of research into nonviral gene delivery has yielded a number of synthetic cationic lipids and polymers with transfection activity.
  • The development of both cationic and anionic exchange materials did not occur until 1935.


Mid 19th century: from cata- 'alongside' or from cathode, + ion.

Words that rhyme with cation

Definition of cation in:
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