Craving pain (4)
I believe the answer is:
ache
This might be a double definition.
'craving' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'pain' is the second definition.
(ache is a kind of pain)
Can you help me to learn more?
(Other definitions for ache that I've seen before include "Dull steady pain" , "Pine" , "Hurt; yearn" , "Nagging pain" , "Take an aspirin for it" .)