Blue feathers thrown (8)
I believe the answer is:
downcast
'blue' is the definition.
(thesaurus)
'feathers thrown' is the wordplay.
'feathers' becomes 'down' (down is a kind of feathers).
'thrown' becomes 'cast' (I've seen this in other clues).
'down'+'cast'='DOWNCAST'
(Other definitions for downcast that I've seen before include "Feeling despondent" , "Low in spirits" , "Dispirited, gloomy" , "Sad" , "Dejected and discouraged" .)