Hit back about woman losing son in gallery (9)
I believe the answer is:
'hit back' is the definition.
(I've seen this before)
'about woman losing son in gallery' is the wordplay.
I cannot quite understand how this works, but
'about' could be 're' ('re' means regarding or about) and 're' is located in the answer.
'woman' could be 'talia' and 'talia' is found in the answer.
The remaining letters 'te' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for retaliate that I've seen before include "Make tit-for-tat attack" , "settle accounts" , "Repay injury with similar one" , "Act in revenge" , "Get revenge" .)