Squawk from a bird (6)
I believe the answer is:
grouse
I believe this clue is a double definition.
'squawk' is the first definition.
(synonyms)
'a bird' is the second definition.
(grouse is a kind of bird)
'from' acts as a link.
(Other definitions for grouse that I've seen before include "Bird - complaint" , "Gripe; game bird" , "No shooting it before 12 August" , "Complain like game bird" , "Game bird - beef" .)