Floor covering that’s wasted i.e. on Mull (8)
I believe the answer is:
linoleum
'floor covering' is the definition.
(I've seen this before)
'wasted i e on mull' is the wordplay.
'wasted' indicates an anagram.
'i'+'e'+'on'+'mull'='ieonmull'
'ieonmull' with letters rearranged gives 'LINOLEUM'.
'that's' acts as a link.
(Other definitions for linoleum that I've seen before include "Common floor covering, often in kitchen" , "Mule/lion cross for a floor covering" , "Type of floor covering" , "Impregnated fabric for the floor" , "Kind of floor covering with shiny surface" .)