Tablet broken in struggle (6)
I believe the answer is:
battle
'struggle' is the definition.
(a struggle or ordeal might be called a battle)
'tablet broken' is the wordplay.
'broken' indicates anagramming the letters.
'tablet' anagrammed gives 'BATTLE'.
'in' is the link.
(Other definitions for battle that I've seen before include "Eg, Bosworth, Blenheim" , "Military fight" , "Wartime set piece" , "Sussex town" , "Fight between armies" .)