Give most appropriate reaction to pain? (6)
I believe the answer is:
bestow
'give' is the definition.
(bestowing is a kind of giving)
'most appropriate reaction to pain?' is the wordplay.
I cannot really understand how this works, but
'to' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bestow that I've seen before include "Confer or award" , "Set bow to give" , "Give as a gift" , "Confer - impart" , "Award, present as a gift" .)