New and revised interpretation of routine output from cyclotron? (8)
I believe the answer is:
neutrino
'output from cyclotron?' is the definition.
(a cyclotron is a type of particle accelerator)
'new and revised interpretation of routine' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'and' is a charade indicator (letters next to each other).
'revised interpretation of' indicates anagramming the letters.
'routine' anagrammed gives 'eutrino'.
'n'+'eutrino'='NEUTRINO'
(Other definitions for neutrino that I've seen before include "Minute item lacking mass" , "Uncharged elementary particle" , "Spinner" , "Subatomic particle, now said to travel faster than light" , "Small piece of matter" .)