He'll admit he's got something (5)
I believe the answer is:
owner
'he'll' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'admit he's got something' is the wordplay.
I cannot really see how this works, but
'admit' could be 'own' (own can mean to admit or acknowledge) and 'own' is located in the answer.
'something' could be 'er' (I've seen this in other clues) and 'er' is present in the answer.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for owner that I've seen before include "The person in legal possession" , "landlord" , "One who has something" , "possessive type" , "The person in lawful possession" .)