Bachelor nursed pain (4)

I believe the answer is:
ache
'pain' is the definition.
(ache is a kind of pain)
'bachelor nursed' is the wordplay.
'ACHE' is hidden in amongst the letters.
But, I'm uncertain how this is indicated.
Can you help me to learn more?
(Other definitions for ache that I've seen before include "Persistent dull pain" , "Pine" , "Long ? pain" , "Dull steady pain" , "Similar" .)
