Badly rusted piece of cleaning equipment (6)
I believe the answer is:
duster
'piece of cleaning equipment' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'badly rusted' is the wordplay.
'badly' is an anagram indicator.
'rusted' with letters rearranged gives 'DUSTER'.
(Other definitions for duster that I've seen before include "Soft cloth for cleaning surface" , "Polishing cloth" , "Cloth for cleaning chalk from blackboard" , "cleaner" , "Cloth for removing surface powder" .)