Crossword Genius

Correct, sport — ion is a particle (8)

Ross

I believe the answer is:

positron

'particle' is the definition.
(I know that positron is a type of antilepton)

'correct sport ion' is the wordplay.
'correct' is an anagram indicator.
'sport'+'ion'='sportion'
'sportion' with letters rearranged gives 'POSITRON'.

'is a' acts as a link.

(Other definitions for positron that I've seen before include "possible contributor to annihilation" , "A tiny thing" , "Charged particle" , "Elementary particle with positive charge" , "Sub-atomic particle" .)

I've seen this clue in The Guardian.
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