Pledge unbounded hate (4)
I believe the answer is:
oath
This might be a double definition.
'pledge' is the first definition.
(I've seen this before)
'unbounded hate' is the second definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
Can you help me to learn more?
(Other definitions for oath that I've seen before include "Tedious task" , "bad language" , "Vow or expletive" , "Curse or solemn word" , "Imprecation" .)