Crew feathers easily (5,4)
I believe the answer is:
hands down
'easily' is the definition.
(synonyms)
'crew feathers' is the wordplay.
'crew' becomes 'hands' (I've seen this before).
'feathers' becomes 'down' (down can mean bird feathers).
'hands'+'down'='HANDS-DOWN'
(Other definitions for hands down that I've seen before include "producing sentences?" , "Common teaching command" , "six-thirty?" , "Teacher's instruction after question's answered" , "extremely easily" .)