The most common and most likely answer to this crossword clue is the 8 letter word POSITRON
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More clues leading to the result POSITRON
- Put forward Weasley as possible contributor to annihilation
- Particle, larger than normal, has it in for most common of neutrinos
- Particle, when realigned, is right on top
- One is charged in sport — after grilling admits nothing
- Assert Collider finally working — here’s a particle
- Moving proton is an elementary particle
- Correct, sport — ion is a particle
Buddy explains!

The straight part
We know that "Particle" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case particle = positron.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 POSITRON mean?
POSITRON noun- The antimatter equivalent of an electron, having the same mass but a positive charge