Long death in hanging (7)
I believe the answer is:
pendant
'hanging' is the definition.
('pendant' can be a synonym of 'hanging')
'long death in' is the wordplay.
'long' becomes 'pant' (I've seen this before).
'death' becomes 'end' ('end' can be a synonym of 'death').
'in' is an insertion indicator.
'pant' placed around 'end' is 'PENDANT'.
(Other definitions for pendant that I've seen before include "item suspended" , "Hanging light" , "One hung by the neck" , "earring, say" , "Ornament hanging from a piece of jewellery" .)