Dull floor covering (3)
I believe the answer is:
mat
This clue is a double definition.
'dull' is the first definition.
(mat as opposed to glossy)
'floor covering' is the second definition.
(a mat is a floor covering)
(Other definitions for mat that I've seen before include "What the cat sat on?" , "To wipe your feet on" , "carpeting" , "Floor-pad" , "Unglossy floor pad" .)