The most common and most likely answer to this crossword clue is the 9 letter word TELEGRAPH
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More clues leading to the result TELEGRAPH
- Communications device to signal unwittingly
- Pin and clip secured by the knotted wire
- Communications system that could be great help
- See 8ac
- Great help unravelling wire
- Member given blame in the shoddy newspaper
- Daily signal
- What about stage talk after time signal?
- Signal for lager — the cocktail requires a drop of Pilsner
- Signal originally heard after English side’s caught in ambush
Buddy explains!

The straight part
We know that "Communications system" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case communications system = telegraph.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 TELEGRAPH mean?
TELEGRAPH noun- An apparatus, or a process, for communicating rapidly between distant points, especially by means of established visible or audible signals representing words or ideas, or by means of words and signs, transmitted by electrical means.
- A visible or audible cue that indicates to an opponent the action that a character is about to take.
- To send a message by telegraph.
- To give nonverbal signals to another, as with gestures or a change in attitude.
- To show one's intended action unintentionally.