Lure me with top off? Crude! (9)
I believe the answer is:
petroleum
'crude' is the definition.
(I know that crude can be written as petroleum)
'lure me with top off?' is the wordplay.
'with' says to put letters next to each other.
'off?' indicates anagramming the letters (I've seen 'off' mean this).
'lure'+'me'='lureme'
'lureme' put after 'top' is 'toplureme'.
'toplureme' is an anagram of 'PETROLEUM'.
(Other definitions for petroleum that I've seen before include "Source of fuel" , "Hydrocarbon oil" , "Fuel oil" , "Hydrocarbon fuel" , "Fossil fuel" .)