Just the chap for a stirring speech (8)
I believe the answer is:
agitator
'stirring speech' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'just the chap for a' is the wordplay.
I cannot really see how this works, but
'for' could be 'to' (eg both can mean 'in the opinion of') and 'to' is found in the answer.
'a' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for agitator that I've seen before include "Fomenter of unrest" , "Agent provocateur" , "Rabble-rouser - blender" , "One stirring up (things)" , "Demagogue" .)