The most common and most likely answer to this crossword clue is the 8 letter word SPIN-OFF
I've seen this crossword clue in The Guardian
S
P
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More clues leading to the result SPIN-OFF
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 SPIN-OFF mean?
SPIN-OFF noun- An offshoot.
- An incidental benefit or unexpected pay-off.
- By-product.
- A fictional work where the protagonist was introduced in a preceding work or at least shares the same setting, often in a different aspect.
- The formation of a subsidiary company that continues the operations of part of the parent company; the company so formed.