Accumulated debris I trusted to be moved (8)
I believe the answer is:
detritus
'accumulated debris' is the definition.
(I've seen this before)
'i trusted to be moved' is the wordplay.
'to be moved' indicates anagramming the letters.
'i'+'trusted'='itrusted'
'itrusted' anagrammed gives 'DETRITUS'.
(Other definitions for detritus that I've seen before include "Any kind of debris" , "Loose eroded matter" , "Waste, debris" , "Left over bits and pieces" , "Accumulated debris" .)