The most common and most likely answer to this crossword clue is the 7 letter word BLEEPER
I've seen this crossword clue in The Times
B
L
E
E
P
E
R
More clues leading to the result BLEEPER
- Censoring device forced rebel to suppress past record
- One might call doctor for blood type before injecting drug into sick person
- Potential energy in rebel set off what may alert police
- Almost drain a device to attract attention
- British PM once coming up on Queen’s comms device
- It receives indication a doctor is required
- Device to alert European that British outcast is around
Buddy explains!
The straight part
We know that "Device to alert" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case device to alert = bleeper.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 BLEEPER mean?
BLEEPER noun- Something or someone that bleeps.
- An electronic device that makes a bleeping sound to obscure certain words, used to censor spoken dialogue.