The most common and most likely answer to this crossword clue is the 6 letter word CONTRA
I've seen this crossword clue in The Daily Telegraph
C
O
N
T
R
A
More clues leading to the result CONTRA
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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 CONTRA mean?
CONTRA noun- A deal to swap goods or services.
- A conservative; originally tied to Nicaraguan counter-revolutionaries.
- An entry (or account) that cancels another entry (or account).
- Any of the musical instruments in the contrabass range, e.g. contrabassoon, contrabass clarinet or, especially, double bass.
- A contra dance.
- A country dance.
- To undo; to reverse.
- Contrary to something
- Against; contrary or opposed to; in opposition or contrast to