Now for the Abstract bit :-)
As for the other replies - you are all correct so I have to be fair and give it to the person who mentioned the word 'Brand' [mainly because I had in mind the phrase The Beckham Brand when I began].
Well done Irouléguy for getting there just before flerdle [with whom I agree wholeheartedly on the annoyance factor]
Commiseration thingies to INJ for also being correct.
*hands over to Irouléguy*
Summary:
It is: a single, existing, permanent, manufactured metal object in the U.K., bigger than a phone box and smaller than a shipping container, big enough to get inside (laughter), at least as wide as tall, um er briefly associated with a TV series, and without moving parts.
It is not: a form of transport, or any of the specific things mentioned so far.