The most common and most likely answer to this crossword clue is the 8 letter word TRIPWIRE
I've seen this crossword clue in The Guardian
T
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More clues leading to the result TRIPWIRE
Buddy explains!
The straight part
We know that "Mine triggered by this/Mine triggered by this" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mine triggered by this/mine triggered by this = tripwire.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 TRIPWIRE mean?
TRIPWIRE noun- A cord or wire arranged so that when snagged or pulled by an intruder, it will trigger a detector or trap or a device, such as a land mine.
- Any means of detecting intruders.
- To set a tripwire mechanism in (a location).