cation

American  

[kat-ahy-uhn, -on] / ˈkætˌaɪ ən, -ɒn /

Or kation

noun

Physical Chemistry.

1. a positively charged ion that is attracted to the cathode in electrolysis.

2. any positively charged atom or group of atoms (opposed to anion).

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cation British  

/ ˈkætaɪən, ˌkætaɪˈɒnɪk /

noun

1. a positively charged ion; an ion that is attracted to the cathode during electrolysis Compare anion

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cation Scientific  

/ kăt′ī′ən /

1. An ion with net positive charge, having more protons than electrons. In electrolysis, cations migrate to a negatively charged cathode.

2. Compare anion

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Other Word Forms

• cationic adjective
• cationically adverb

Etymology

Origin of cation

1825–35; < Greek katión going down (neuter of katiṓn, present participle of kateînai ), equivalent to kat- cat- ( def. ) + -i- go + -on neuter present participle suffix

Explanation

In science, a cation is an ion, or charged particle, with a positive charge. In other words, a cation has more protons than electrons. If you come across the word ion in a chemistry or physics class, cation and anion won't be far behind. An ion is a particle that has an electrical charge. When an ion's charge is negative, it's more specifically called an anion, and when it's positive, you can use the term cation. The Greek source is kation, which means "going down."

Example Sentences

He recommends treating the issue at the water point of entry to the home with cation exchange resin, a type of ion exchange.

From Los Angeles Times • Jul. 22, 2024

They are made of an A+ cation, a B2+ divalent cation, and an X- halide.

From Science Daily • Feb. 29, 2024

A general strategy to enhance the proton conductivity in such perovskites is to introduce an acceptor dopant; that is, a cation M3+ with a valence lower than that of B4+.

From Science Daily • Nov. 21, 2023

Through advanced atomic-scale measurements and calculations, the team found that these interlayer transition metal ions act as a "cap" above or below the honeycomb structure, preventing cation migration and maintaining stability.

From Science Daily • Sep. 28, 2023

Both contain iron, it is true, but neither possess the properties of the cation Fe+++, but rather those of the complex anion of which they form a part.

From The Mechanism of Life by Leduc, Stéphane