Bird in Aeneid erased (5)
I believe the answer is:
eider
'bird' is the definition.
(eider is a kind of bird)
'in aeneid erased' is the wordplay.
'in' indicates the answer is hidden within the clue.
'EIDER' can be found hidden inside 'aeneid erased'.
(Other definitions for eider that I've seen before include "Duck from which down is obtained" , "Down comes from this" , "Species of duck" , "Large sea duck" , "Sea-duck" .)