The most common and most likely answer to this crossword clue is the 8 letter word TELECAST
I've seen this crossword clue in The Times
T
E
L
E
C
A
S
T
More clues leading to the result TELECAST
- Eg a TV play, or its players
- Test entered by the French chartered accountant — something to watch
- Select at random what’s on the box
- Select at random what’s on TV
- Funny tales etc. featured in what’s seen on the box
- Select a revised time for programme to be seen
- Empty the ruined castle for transmission
- Transmission expert left to reflect during trial
Buddy explains!

The straight part
We know that "Transmission" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case transmission = telecast.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 TELECAST mean?
TELECAST noun- A television broadcast, especially outside of a studio.
- To broadcast by television.
- To broadcast a television program.