Bear backing old English bird (6)
I believe the answer is:
hoopoe
'bird' is the definition.
(hoopoe is a kind of bird)
'bear backing old english' is the wordplay.
'bear' becomes 'pooh' (Winnie the Pooh).
'backing' is a reversal indicator.
'old english' becomes 'OE'.
'pooh' in reverse letter order is 'hoop'.
'hoop'+'oe'='HOOPOE'
(Other definitions for hoopoe that I've seen before include "Flier" , "Crested bird, pink with black and white wings" , "Pink Eurasian bird with black and white wings and tail" , "Bird with curved bill" , "occasional visitor here" .)