Bird initially making a sound like a crow (5)
I believe the answer is:
macaw
'bird' is the definition.
(macaw is a kind of bird)
'initially making a sound like a crow' is the wordplay.
'initially' says to take the initial letters.
'sound like a crow' becomes 'caw'.
The first letter of 'making' is 'm'.
'm'+'a'+'caw'='MACAW'
(Other definitions for macaw that I've seen before include "Chattering cousin of a cockatoo" , "colourful flyer" , "brilliant winger" , "Colourful creature" , "Brightly-coloured parrot" .)