Cryptic crossword clue
Mad queen imprisoned in Berks improperly

The most common and most likely answer to this crossword clue is the 7 letter word BERSERK

I've seen this crossword clue in The Guardian
B
E
R
S
E
R
K

Buddy explains!

The straight part
We know that "Mad" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mad = berserk.
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 BERSERK mean?

BERSERK noun
  1. A crazed Norse warrior who fought in a frenzy; a berserker.
BERSERK adjective
  1. Injuriously, maniacally, or furiously violent or out of control.
  2. Weird; bizarre.

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