The most common and most likely answer to this crossword clue is the 9 letter word SERIOUSLY
I've seen this crossword clue in The Guardian
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More clues leading to the result SERIOUSLY
Buddy explains!
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 SERIOUSLY mean?
SERIOUSLY adverb- (manner) In a serious or literal manner.
- Gravely; deeply; very much.
- Used to attempt to introduce a serious point in a less serious conversation
- Used to call back to a previous point, either in disbelief or emphasis