Lame actors this man dismissed from operas (9)
I believe the answer is:
hamstring
'lame' is the definition.
(I know that hamstring is a type of lame)
'actors this man dismissed from operas' is the wordplay.
'actors' becomes 'hams' (ham is a kind of actor).
'this man' becomes 'he' (pronoun for a man).
'dismissed from' suggests deleting specific letters.
'operas' becomes 'The Ring' (The Ring, cycle of operas by Richard Wagner).
'thering' with 'he' taken out is 'tring'.
'hams'+'tring'='HAMSTRING'
(Other definitions for hamstring that I've seen before include "Thwart, severely restrict" , "Tendon behind the knee" , "Tendons at back of the knee" , "Cramp the style of" , "Tendon at back of knee" .)