The portion of an enclosed area which contains air, especially breathable air.
that part of the sky designated for the sole use of aircraft.
The cavity in a cavity wall containing air for insulation.
Space (i.e. a few neighboring frequencies) available for broadcasting within a particular frequency band.
A specified portion of the atmosphere, especially that under the technical aviation control and/or jurisdiction of a particular state over which territory (and territorial waters) it lies.
Fresh air, especially that breathed at the seaside and smelling of seaweed.
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.
Hypernym: greenhouse gas
To treat with ozone.