The most common and most likely answer to this crossword clue is the 7 letter word BLABBER
I've seen this crossword clue in The Guardian
B
L
A
B
B
E
R
More clues leading to the result BLABBER
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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 BLABBER mean?
BLABBER noun- A person who blabs; a tattler; a telltale.
- To blather; to talk foolishly or incoherently.
- To blab; to reveal a secret.
- To stick out one's tongue.