Made for strength in the end (8)
I believe the answer is:
enforced
'made for' is the definition.
Although both the answer and definition are past participle verbs, I can't see how they can define each other.
'strength in the end' is the wordplay.
'strength' becomes 'force' (synonyms).
'in' means one lot of letters goes inside another.
'force' put within 'end' is 'ENFORCED'.
Can you help me to learn more?
(Other definitions for enforced that I've seen before include "Taken effect" , "Imposed" , "Caused laws to be observed" , "'Compelled observance of, a law say (8)'" , "Compulsory" .)