Sheet material lion and mule destroyed (8)
I believe the answer is:
linoleum
'sheet material' is the definition.
'linoleum' can be an answer for 'material' (linoleum is a kind of material). I am not certain of the 'sheet' bit.
'lion and mule destroyed' is the wordplay.
'and' means one lot of letters go next to another.
'destroyed' indicates an anagram.
'lion' after 'mule' is 'mulelion'.
'mulelion' with letters rearranged gives 'LINOLEUM'.
Can you help me to learn more?
(Other definitions for linoleum that I've seen before include "Type of floor covering" , "Kind of floor covering with shiny surface" , "Mule/lion cross for a floor covering" , "Impregnated fabric for the floor" , "Canvas-backed floor covering" .)