The most common and most likely answer to this crossword clue is the 3 plus 8 letter word NON SEQUITUR
I've seen this crossword clue in The Guardian
N
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Q
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More clues leading to the result NON SEQUITUR
- Hurry up fielding strange question, giving illogical answer
- Either he’s dead or my watch has stopped? Awkward question: run with it!
- Hurry up framing silly question’s silly reply
- Bizarre question in reversed sequence that doesn’t follow
- It doesn’t follow that nurse quit on being redeployed
- Wrong conclusion? Run question a different way
Buddy explains!

The straight part
We know that "Either he’s dead or my watch has stopped?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case either he’s dead or my watch has stopped? = non sequitur.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.