Parrot shows resplendence with head concealed (4)
I believe the answer is:
lory
'parrot' is the definition.
(term for a small parrot)
'resplendence with head concealed' is the wordplay.
'resplendence' becomes 'glory' (synonyms).
'with head concealed' means to remove the first letter (head can mean the first letter).
'glory' with its first letter taken off is 'LORY'.
'shows' is the link.
(Other definitions for lory that I've seen before include "Small parrot" , "Australasian parrot" .)