Curse little devil, worried about leisure facility (9)
I believe the answer is:
imprecate
'curse' is the definition.
(I know that curse can be written as imprecate)
'little devil worried about leisure facility' is the wordplay.
'little devil' becomes 'imp' (an imp is a little demon).
'worried' becomes 'ate' (something worrying may eat someone up).
'about' is a charade indicator (letters next to each other).
'leisure facility' becomes 'rec' (short for recreation ground).
'ate' after 'rec' is 'recate'.
'imp'+'recate'='IMPRECATE'
(Other definitions for imprecate that I've seen before include "Swear" , "Put curse on (someone)" , "Invoke evil -- crime tape (anag)" .)