The most common and most likely answer to this crossword clue is the 3 plus 6 letter word AIR GUITAR
I've seen this crossword clue in Independent
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More clues leading to the result AIR GUITAR
- Insubstantial contribution to popular music?
- Mimed playing song? It’s caught by screen, briefly
- AIR GUITAR
- Instrument invented by plucky performer?
- Instrument you imagine is involved in heavy metal?
- Imagined axe slashed a rug — it cut into screen
- Whereon plucky action occurs in one’s mind
- Chuck Berry’s fabulous jam?
- It doesn’t take any pluck to play this
- An unreal plaything with no strings attached?
Buddy explains!

The straight part
We know that "AIR GUITAR (an imaginary GUITAR played by someone miming the actions of real player)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case air guitar (an imaginary guitar played by someone miming the actions of real player) = air guitar.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.