The most common and most likely answer to this crossword clue is the 4 letter word CAGE
I've seen this crossword clue in The Daily Telegraph
C
A
G
E
More clues leading to the result CAGE
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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 CAGE mean?
CAGE noun- An enclosure made of bars, normally to hold animals.
- The passenger compartment of a lift.
- (water polo) The goal.
- An automobile.
- Something that hinders freedom.
- The area from which competitors throw a discus or hammer.
- An outer framework of timber, enclosing something within it.
- A skeleton frame to limit the motion of a loose piece, such as a ball valve.
- A wirework strainer, used in connection with pumps and pipes.
- The drum on which the rope is wound in a hoisting whim.
- The catcher's wire mask.
- A regular graph that has as few vertices as possible for its girth.
- To confine in a cage; to put into and keep in a cage.
- To restrict someone's movement or creativity.
- To track individual responses to direct mail, either to maintain and develop mailing lists or to identify people who are not eligible to vote because they do not reside at the registered addresses.