Prince Henry has a ring, a holy ring (4)
I believe the answer is:
halo
'a holy ring' is the definition.
(I've seen this before)
'prince henry has a ring' is the wordplay.
I cannot really see how this works, but
'prince' could be 'hal' (Shakespearean nickname of Henry V when a prince) and 'hal' is found within the answer.
'ring' could be 'o' (O is the shape of a ring) and 'o' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for halo that I've seen before include "Light around sun, saint" , "Symbol of sainthood" , "Luminous ring" , "Holy ring" , "Glittering aura" .)