The most common and most likely answer to this crossword clue is the 12 letter word FIDDLESTICKS
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More clues leading to the result FIDDLESTICKS
- Tampers with some marks on exam paper? Nonsense
- Cheats receiving criticism for such nonsense
- Toy bear’s in bunk
- Musical instrument jams — blow it!
- Instrument is tacky, darn it!
- Violinists' bows rot
- Cobblers found in Bow and Sweden
- Cheats accepting punishment for nonsense
- Instrument won’t shift rubbish!
- Rubbish played on violins
Buddy explains!

The straight part
We know that "Rubbish" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rubbish = fiddlesticks.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 FIDDLESTICKS mean?
FIDDLESTICKS noun- A bow used to play the fiddle.
- Nonsense! Expresses dismissal or disdain.
- Darn! Expresses mild dismay or annoyance.