ENGLISH
REFERENCE

cation

n. countable
C1 Advanced US //ˈkæˌtaɪən// UK //kˈætaɪən// cation

n. a positively charged particle in a chemical solution. It moves toward the negative side of an electrical current.

n. a positively charged ion that is attracted to the cathode during electrolysis. In chemical notation, it is typically represented by a superscript plus sign following the element symbol.


SIMPLE

Sodium ions are common cations in salt water.

CONTEXTUAL

During the electrolysis of water, the cation moves toward the cathode while the anion moves toward the anode.

COMPLEX

The movement of cations through the cell membrane is essential for generating the electrical impulses that allow neurons to communicate with one another.

Origin

Learned borrowing from Ancient Greek κᾰτῐόν (kătĭón), neuter present participle of κᾰ́τειμῐ (kắteimĭ, “to go down, come down”), from κᾰτᾰ- (kătă-, “downwards, down, cata-”) + εἶμῐ (eîmĭ, “to go, come”). Coined by English polymath William Whewell in 1834 for Michael Faraday, who introduced it later that year. By surface analysis, cat(a)- + ion.

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