I had antique briefly, one much admired (4)
I believe the answer is:
idol
'one much admired' is the definition.
(I've seen this before)
'i had antique briefly' is the wordplay.
'i had' becomes 'i'd' (contraction).
'antique' becomes 'old' (similar in meaning).
'briefly' means to remove the last letter.
'old' with its final letter taken off is 'ol'.
'id'+'ol'='IDOL'
(Other definitions for idol that I've seen before include "Worshipped figure (not painting); revered person" , "Sacred image" , "Worshipped image; lido (anag.)" , "Person who is the object of intense admiration as by fan club" , "Subject of adoration, may be graven" .)