The most common and most likely answer to this crossword clue is the 4 plus 2 letter word ACTS UP
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More clues leading to the result ACTS UP
- When to hold court, leading horses around
- A cadet’s outside with drink and behaves badly
- New cast at university behaves badly
- Book finished, throws a tantrum
- Behaves badly, having drink after do
- One caught short with drink is a 29
- Behaves badly when taught with Biblical text
- Behaves like a luvvie elevated – is a pain in the arse
- Poor cast at university – performs awkwardly
- Misbehaves and turns on pump regularly
Buddy explains!

The straight part
We know that "behaves badly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case behaves badly = acts up.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.