The most common and most likely answer to this crossword clue is the 12 letter word TRANSMISSION
I've seen this crossword clue in Financial Times
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More clues leading to the result TRANSMISSION
- Brown’s undertaking involving king’s broadcast
- Neutrois calling for broadcast
- Conveyance in one’s car
- Broadcast teaches one to leave before operation
- Insist Romans misrepresented in broadcast
- Conveyance? One goes in one’s car
- Programme for passing on: Top Gear and all connected with it
- Broadcast second undertaking by one dropping out of school
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TRANSMISSION mean?
TRANSMISSION noun- The act of transmitting, e.g. data or electric power.
- The fact of being transmitted.
- Something that is transmitted, such as a message, picture or a disease; the sending of such a thing.
- The passage of a nerve impulse across synapses.
- An assembly of gears through which power is transmitted from the engine to the driveshaft in a motor car / automobile; a gearbox.
- The right possessed by an heir or legatee of transmitting to his successor(s) any inheritance, legacy, right, or privilege, to which he is entitled, even if he should die without enjoying or exercising it.
- (medicine, biology) The passing of a communicable disease from an infected host individual or group to a conspecific individual or group.