ozone

An allotrope of oxygen (symbol O₃) having three atoms in the molecule instead of the usual two; it is a toxic gas, generated from oxygen by electrical discharge.uncountableusually

• Lightning flashed again, the thunder came a second later. It rained harder. The smell of ozone was strong. You could feel the charge in the air.
• Martin said that the National Park Service invested in “a state-of-the-art ozone nanobubbler filtration system” that is intended to keep algae out.

Fresh air, especially that breathed at the seaside and smelling of seaweed.UKinformaluncountable

• To Ramsgate baths she sped, in quest / Of seaweed and ozone ; / For seaweed and ozone were best, / They said, to give her tone.
• It's got the lot: fresh sea air, ozone, seaweed. You could cut the air with a knife.

To treat with ozone.transitive

• Whenever it exists, as it usually does, even where the tide water freshens at the ebb, it seems to have a purifying tendency, probably by ozoning the superincumbent atmosphere.
• I worked nonstop to make the house safe. Periodically I ozoned the first-floor bathroom, but it still made us sick.