Demolition debris (6)
I believe the answer is:
rubble
'demolition debris' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rubble that I've seen before include "Waste fragments of stone or rock, debris" , "Remains of demolished building" , "Bits of demolished building" , "Lose stones" , "Light theatrical show" .)