The most common and most likely answer to this crossword clue is the 4 letter word CONK
I've seen this crossword clue in Financial Times
C
O
N
K
More clues leading to the result CONK
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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 CONK mean?
CONK noun- A marine gastropod of the family Strombidae which lives in its own spiral shell.
- The shell of this sea animal.
- A musical instrument made from a large spiral seashell, somewhat like a trumpet.
- The semidome of an apse, or the apse itself.
- A machine (rather like a rotating pestle and mortar) used to refine the flavour and texture of chocolate by warming and grinding.
- A person who operates such a machine.
- The shelf- or bracket-shaped fruiting body of a bracket fungus (also called a shelf fungus), i.e. a mushroom growing off a tree trunk.
- A nose, especially a large one.
- To hit, especially on the head.
- A hairstyle involving the chemical straightening and styling of kinky hair.
- To chemically straighten tightly curled hair.
- (often with out) To fail or show signs of failing, cease operating, break down, become unconscious.