Space (i.e. a few neighboring frequencies) available for broadcasting within a particular frequency band.
that part of the sky designated for the sole use of aircraft.
The cavity in a cavity wall containing air for insulation.
The portion of an enclosed area which contains air, especially breathable air.
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.
The frequency at which bits (binary digits) pass a given physical or metaphorical point, measured in bps (bits per second).