Priest very briefly appearing in garland (4)
I believe the answer is:
levi
'priest' is the definition.
(biblical figure)
'very briefly appearing in garland' is the wordplay.
'very briefly' becomes 'v' (abbreviation; 'briefly' asks for a short form).
'appearing in' is an insertion indicator.
'garland' becomes 'lei' (synonyms).
'v' placed within 'lei' is 'LEVI'.
(Other definitions for levi that I've seen before include "Tribe of Israel" , "Hebrew patriarch - Italian writer" , "Primo -, It. novelist" , "Hebrew patriarch, son of Jacob" , "Tribe - name for Strauss" .)