Revolutionary extends expression for a cat? (7)
I believe the answer is:
cheetah
'cat?' is the definition.
(cheetah is a kind of cat)
'revolutionary extends expression for a' is the wordplay.
I cannot really understand how this works, but
'revolutionary' could be 'che' (Che Guevara the Marxist revolutionary) and 'che' is found within the answer.
'a' is found in the answer.
The remaining letters 'eth' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for cheetah that I've seen before include "Swift predator" , "Swiftest mammal" , "Long-legged feline" , "Animal that's remarkably quick" , "Spotted swift big cat" .)