Unacceptable, as punishment (5)
I believe the answer is:
cruel
(Other definitions for cruel that I've seen before include "Brutal" , "Deliberately and pitilessly causing pain" , "Diabolical" , "Merciless" , "Painful" .)
I believe the answer is:
cruel
(Other definitions for cruel that I've seen before include "Brutal" , "Deliberately and pitilessly causing pain" , "Diabolical" , "Merciless" , "Painful" .)