The most common and most likely answer to this crossword clue is the 6 plus 6 letter word KNIGHT ERRANT
I've seen this crossword clue in Financial Times
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More clues leading to the result KNIGHT ERRANT
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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.
Crossword Answer definitions
KNIGHT ERRANT noun- A knight in a medieval romance who wanders in search of adventure and opportunities to prove his chivalry.
- A person who displays an adventurous or a quixotic spirit.