The cavity in a cavity wall containing air for insulation.
that part of the sky designated for the sole use of aircraft.
The portion of an enclosed area which contains air, especially breathable air.
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.
A pocket of vapour inside a fluid flow, created by cavitation.
An empty place; A location that has nothing useful.
An empty space; a vacuum.
A collection of adjacent vacancies inside a crystal lattice.
An extended region of space containing no galaxies.
An empty space between floors or walls, including false separations and planned gaps between a building and its facade.
A black cat.
That does not return a value; a procedure.
Containing nothing; empty; not occupied or filled.
Having no incumbent; unoccupied; said of offices etc.
Being without; destitute; devoid.
Containing no immaterial quality; destitute of mind or soul.
Not producing any effect; ineffectual; vain.
Of no legal force or effect, incapable of confirmation or ratification.
To make invalid or worthless.
To throw or send out; to evacuate; to emit; to discharge.
To empty.