The most common and most likely answer to this crossword clue is the 3 plus 4 plus 4 plus 4 letter word LET ONES HAIR DOWN
I've seen this crossword clue in Independent
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More clues leading to the result LET ONES HAIR DOWN
- Party — free do?
- Release inhibitions? Soon draw the line, as ordered
- Act in a free way and dismantle your beehive?
- Act wildly — drop one's capital cover?
- Where old nations reassembled to act without reserve
- Drop bun party
- What Rapunzel did is shed inhibitions
- Behave uninhibitedly and don’t secure the locks?
Buddy explains!
The straight part
We know that "to act without reserve" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case to act without reserve = let ones hair down.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.