Repeatedly bomb China (8)
I believe the answer is:
eggshell
'china' is the definition.
(I've seen this before)
'repeatedly bomb' is the wordplay.
'repeatedly' becomes 'egg' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'bomb' becomes 'shell' (shelling is a kind of bombing).
'egg'+'shell'='EGGSHELL'
Can you help me to learn more?
(Other definitions for eggshell that I've seen before include "Type of paint finish" , "(Of paint) having a very slight sheen" , "manufactured in layers?" , "cracker?" , "Type of translucent porcelain" .)