The most common and most likely answer to this crossword clue is the 9 letter word EARWIGGED
I've seen this crossword clue in Independent
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More clues leading to the result EARWIGGED
- Listened in with appreciation, then reprimanded
- Agreed working to fix rug was a bugger!
- Tried to listen with attention, like a judge
- Illicitly picked up unopened equipment under rug
- Listened secretly as barrister mentioned this place in Bow earlier
- Listened in with attention like a judge
- Intercepted communications stirred up war I urged on both sides
Buddy explains!

The straight part
We know that "Listened secretly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case listened secretly = earwigged.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 EARWIGGED mean?
EARWIGGED verb- To fill the mind of with prejudice by insinuations.
- To attempt to influence by persistent confidential argument or talk.
- To eavesdrop.
- To eavesdrop on.