Antimatter conjecture overlaps with 80's sci-fi (8)
I believe the answer is:
positron
'antimatter' is the definition.
(I know that positron is a type of antilepton)
'conjecture overlaps with 80's sci-fi' is the wordplay.
I cannot quite see how this works, but
'conjecture' could be 'posit' (I've seen this in another clue) and 'posit' is located in the answer.
The remaining letters 'ron' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for positron that I've seen before include "there's a small charge here" , "Elementary particle with positive charge" , "Sub-atomic particle" , "Charged particle" , "possible contributor to annihilation" .)