The most common and most likely answer to this crossword clue is the 9 letter word EAVESDROP
I've seen this crossword clue in Independent
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More clues leading to the result EAVESDROP
- Listen in secretly, tumbling over spade
- What happens in autumn with departure of the first bug
- Listen into tip-off for what happens in Autumn
- Parts of roof fall away, exposing a snoop
- . Listen as Cockney retches by sink
- Pulls out of hospital procedure after doctor gives you bug
- Covertly obtain report of First Lady and doctor blocking concession
- Overhear what happens in autumn, but not the start
- Spy, one right out of abandoned Verdi operas
- Tap overspread ground right away
Buddy explains!

The straight part
We know that "Overhear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case overhear = eavesdrop.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 EAVESDROP mean?
EAVESDROP noun- The dripping of rain from the eaves of a house
- The space around a house on which such water drips
- A concealed aperture through which an occupant of a building can surreptitiously listen to people talking at an entrance to the building
- The act of intentionally hearing a conversation not intended to be heard
- To hear a conversation one is not intended to hear; to listen in.
- To listen for another organism's calls, so as to exploit them.