Subject to lower temperature, one might dispense brandy (5)
I believe the answer is:
optic
'subject' is the definition.
Although both the answer and definition are adjectives, I cannot understand how one could define the other.
'lower temperature one might dispense brandy' is the wordplay.
I cannot quite see how this works, but
'temperature' could be 't' (abbreviation) and 't' is located in the answer.
'one' could be 'o' (I've seen this in other clues) and 'o' is found in the answer.
The remaining letters 'pic' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for optic that I've seen before include "Publican's measuring device" , "Eye - spirit measure" , "Spirits measurer" , "Like a sort of nerve" , "Pub measuring device" .)