Where you can store really cool stuff that's rapidly disappearing (3,5)
I believe the answer is:
ice shelf
'where you can store really cool' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'stuff that's rapidly disappearing' is the wordplay.
I cannot quite see how this works, but
'stuff' could be 'ice' (I have seen 'Cold stuff' mean 'ice' so perhaps 'stuff' could also mean 'ice') and 'ice' is found in the answer.
The remaining letters 'shelf' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for ice shelf that I've seen before include "frozen topping" , "Floating frozen sheet attached to land" .)