Retaliatory action causing material and title be returned to nearly all (8)
I believe the answer is:
reprisal
'retaliatory action' is the definition.
(I've seen this before)
'causing material and title be returned to nearly all' is the wordplay.
'causing material' becomes 'rep' (I can't explain this - if you can you should believe this answer much more).
'and' says to put letters next to each other.
'title' becomes 'sir' (I've seen this before).
'be returned' is a reversal indicator (I've seen 'is returned' mean this).
'to nearly all' becomes 'al'.
'sir' reversed gives 'ris'.
'rep'+'ris'+'al'='REPRISAL'
Can you help me to learn more?
(Other definitions for reprisal that I've seen before include "Counterattack" , "Retaliatory deed" , "hitting back" , "Tit for tat" , "comeback" .)