Bachelor's pain (4)
I believe the answer is:
ache
'pain' is the definition.
(ache is a kind of pain)
'bachelor's' is the wordplay.
'ACHE' is hidden within the letters.
However, I'm uncertain how this is indicated.
Can you help me to learn more?
(Other definitions for ache that I've seen before include "Cause pain" , "agony" , "Dull continuous pain" , "Suffer dull pain" , "anguish" .)