Question expert posed about neutron, sceptically (7)
I believe the answer is:
askance
'posed about neutron sceptically' is the definition.
I can't tell whether this definition defines the answer.
'question expert' is the wordplay.
'question' becomes 'ask' (asking a question).
'expert' becomes 'ance' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ask'+'ance'='ASKANCE'
Can you help me to learn more?
(Other definitions for askance that I've seen before include "Sideways (of look)" , "With suspicion or disapproval" , "A look like this is sidelong or suspicious" , "Distrustfully" , "(Look) suspiciously or sceptically" .)