A beast in distress lowers (6)
I believe the answer is:
abates
'lowers' is the definition.
(I've seen this before)
'a beast in distress' is the wordplay.
'in distress' is an anagram indicator.
'beast' anagrammed gives 'bates'.
'a'+'bates'='ABATES'
(Other definitions for abates that I've seen before include "has a fall" , "Grows less intense" , "moderates" , "Becomes less strong like storm" , "Slacks off" .)