The most common and most likely answer to this crossword clue is the 8 letter word AFFIXING
I've seen this crossword clue in Financial Times
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More clues leading to the result AFFIXING
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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 AFFIXING mean?
AFFIXING verb- To attach.
- To subjoin, annex, or add at the close or end; to append to.
- To fix or fasten figuratively; with on or upon.
- Affixation
- Of the function or role of an affix