The most common and most likely answer to this crossword clue is the 7 letter word *SORRY*
I've seen this crossword clue in The Guardian
*
S
O
R
R
Y
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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 *SORRY* mean?
*SORRY* noun- The act of saying sorry; an apology.
- (of a person) Regretful for an action; grieved or saddened, especially by the loss of something or someone.
- Poor, pitifully sad or regrettable.
- Pathetic and inferior to the point of causing others disgust.
- Expresses regret, remorse, or sorrow.
- Used as a request for someone to repeat something not heard or understood clearly.
- Used to correct oneself in speech.