Dead man's chest? (6)
I believe the answer is:
casket
'chest?' is the definition.
(I have seen 'Small chest' mean 'casket' so perhaps 'chest' could also mean 'casket')
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for casket that I've seen before include "Small box to hold jewels" , "Coffin or jewellery box" , "Ornamental box" , "Box for jewellery, or corpse" , "Small box or chest" .)