Trial said to include case for defence (6)
I believe the answer is:
ordeal
'trial' is the definition.
(I've seen this in another clue)
'said to include case for defence' is the wordplay.
'said' becomes 'oral' (both can mean spoken).
'to include' means one lot of letters goes inside another.
'case for' means to remove the middle letters (the letters which encase the others are used).
'defence' with its centre taken out is 'de'.
'oral' placed around 'de' is 'ORDEAL'.
(Other definitions for ordeal that I've seen before include "Difficult or arduous experience" , "Prolonged distressing experience" , "Ancient form of trial" , "Horrible experience" , "A difficult or harrowing time" .)