The most common and most likely answer to this crossword clue is the 8 letter word SMARTASS
I've seen this crossword clue in Independent
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More clues leading to the result SMARTASS
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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 SMARTASS mean?
SMARTASS noun- One who is particularly insolent, who tends to make snide remarks or jokes.
- To talk like a smartass, with a lot of snide remarks.
- Related to or characteristic of a smartass.