The most common and most likely answer to this crossword clue is the 8 letter word FEISTIER
I've seen this crossword clue in The Daily Telegraph
F
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S
T
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More clues leading to the result FEISTIER
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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 FEISTIER mean?
FEISTIER adjective- Tenacious, energetic, spunky.
- Belligerent; prepared to stand and fight, especially in spite of relatively small stature or some other disadvantage.
- Easily offended and ready to bicker.