Sound of distress from good horse (5)
I believe the answer is:
groan
'sound of distress' is the definition.
(I've seen this in another clue)
'good horse' is the wordplay.
'good' becomes 'g' (abbreviation).
'horse' becomes 'roan' (roan is a kind of horse).
'g'+'roan'='GROAN'
'from' is the link.
(Other definitions for groan that I've seen before include "Cry of pain or despair" , "See 18 Down" , "Sound of one in pain" , "Utterance expressing pain or disapproval" , "express disapproval" .)