The most common and most likely answer to this crossword clue is the 8 letter word STITCHED
I've seen this crossword clue in The Guardian
S
T
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C
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D
More clues leading to the result STITCHED
Buddy explains!
The straight part
We know that "What sewer did" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what sewer did = stitched.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 STITCHED mean?
STITCHED verb- To form stitches in; especially, to sew in such a manner as to show on the surface a continuous line of stitches.
- To sew, or unite or attach by stitches.
- To practice/practise stitching or needlework.
- To form land into ridges.
- To weld together through a series of connecting or overlapping spot welds.
- (graphics) To combine two or more photographs of the same scene into a single image.
- (more generally) To include, combine, or unite into a single whole.