I want to ask you something, Ms. Ionescu.

Mrs. Ionescu, I'd like to ask you something.

Lithium ion batteries are used in almost all electric vehicles.

This air cleaner came pretty cheap when I bought it, but I'm rather suspicious of the "negative ions" it produces.

What is an ionic bond?

The black hole is surrounded by a rotating disk of ionized gas.

Positive ions are called cations.

Mercuric nitrate is an ionic compound.

This spacecraft is powered by ion thrusters.

Far from being an empty void, the space around Earth is a jungle of invisible fields and tiny particles. It’s draped with twisted magnetic field lines and swooping electrons and ions.