Singer looking about 50 (8)
I believe the answer is:
starling
'singer' is the definition.
(starling is a kind of birdanimal)
'looking about 50' is the wordplay.
I cannot really understand how this works, but
'about' could be 'a' (abbreviation in Chambers) and 'a' is found in the answer.
'50' could be 'l' (Roman numeral) and 'l' is located in the answer.
The remaining letters 'string' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for starling that I've seen before include "Might Gran list badly for the bird" , "flier" , "Dark, glossy bird" , "Gregarious bird" , "The bird is a good mimic" .)