ENGLISH
REFERENCE

ions

n. countable
C1 Advanced US //ˈaɪˌɑnz// UK //ˈaɪɒnz// ions

n. tiny particles that have an electric charge. They are formed when an atom or molecule loses or gains electrons.

n. atoms or molecules that have gained or lost one or more valence electrons, giving them a net positive or negative electrical charge.


SIMPLE

Salt dissolves in water to form positive and negative ions.

CONTEXTUAL

The battery works by moving lithium ions between the two electrodes to store and release energy.

COMPLEX

In the upper atmosphere, solar radiation strips electrons from gas molecules, creating a layer of ions and free electrons known as the ionosphere.

Synonyms
Usage

Almost always used in the plural when discussing chemical processes or electricity.

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