Wanting Cliff covers to compile (6)
I believe the answer is:
scarce
'wanting' is the definition.
(I've seen this before)
'cliff covers to compile' is the wordplay.
'cliff' becomes 'scar' (I've seen this before).
'covers' says to hollow out the word (remove centre letters) (I've seen 'covers of' mean this).
'compile' with its centre taken out is 'ce'.
'scar'+'ce'='SCARCE'
(Other definitions for scarce that I've seen before include "Uncommon" , "Not often found" , "Not enough to meet demand" , "Deficient in quantity" , "Rare shock Conservative getting in" .)