Die frozen stiff (3,4)
I believe the answer is:
ice cube
'die frozen stiff' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'die frozen' is the wordplay.
I cannot really see how this works, but
'die' could be 'cube' (I've seen this in another clue) and 'cube' is present in the answer.
'frozen' could be 'ice' (I've seen this in other clues) and 'ice' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for ice cube that I've seen before include "It's used for cooling drinks" , "Block used in cold drinks" , "Something frozen" , "Cooling addition to drink" , "Six-faced frozen cooler" .)