Lily has a special house key (8)
I believe the answer is:
asphodel
'lily' is the definition.
(I've seen this before)
'a special house key' is the wordplay.
'special' becomes 'sp'.
'house' becomes 'ho' (abbreviation for house).
'key' becomes 'del' (del key on a keyboard).
'a'+'sp'+'ho'+'del'='ASPHODEL'
'has' acts as a link.
(Other definitions for asphodel that I've seen before include "Lad hopes (anag) - flower" , "Flower of lily family - old heaps (anag)" , "Lily-like plant, the flower of death to ancient Greeks" , "blooms from Elysian fields" , "Old shape (anag) - plant" .)