Bones from carcass lying around (5)
I believe the answer is:
sacra
'bones' is the definition.
(sacrum is a kind of bone)
'from carcass lying around' is the wordplay.
'from' indicates a hidden word.
'lying around' shows that the letters should be reversed in order.
'arcas' can be found hidden inside 'carcass'.
'arcas' reversed gives 'SACRA'.
(Other definitions for sacra that I've seen before include "Triangular bones" , "Bones that form the human pelvic arch" .)