Blue feathers shed from the body (8)

I believe the answer is:

downcast

I'm a little stuck... Click here to teach me more about this clue!

'blue' is the definition.
(I know that blue can be written as downcast)

'feathers shed from the body' is the wordplay.
'feathers' becomes 'down' (down can mean bird feathers).
'shed from the body' becomes 'cast' (I can't explain this - if you can you should believe this answer much more).
'down'+'cast'='DOWNCAST'

Can you help me to learn more?

(Other definitions for downcast that I've seen before include "Dispirited, gloomy" , "Melancholic" , "Dejected and discouraged" , "directed towards ground" , "Low in spirits" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.