Eleven pies put out for the fairies (6)
I believe the answer is:
pixies
'the fairies' is the definition.
(pixy is a kind of fairy)
'eleven pies put out' is the wordplay.
'eleven' becomes 'xi' (Roman numerals).
'put out' indicates putting letters inside.
'xi' inserted into 'pies' is 'PIXIES'.
'for' is the link.
(Other definitions for pixies that I've seen before include "Elves, imps" , "small fairies in children's tales" , "Small supernatural beings in fairy tales" , "Little (mischievous) people" , "Mischievous fairies" .)