Very fat figure turns and runs before sumo wrestling (8)
I believe the answer is:
enormous
'very fat' is the definition.
(enormous can mean very large)
'figure turns and runs before sumo wrestling' is the wordplay.
'figure' becomes 'one' (a numerical figure).
'turns' says the letters should be written backwards.
'and' says to put letters next to each other.
'runs before' becomes 'r' (cricket abbreviation. I am not sure about the 'before' bit.).
'wrestling' indicates anagramming the letters.
'one' backwards is 'eno'.
'sumo' anagrammed gives 'mous'.
'eno'+'r'+'mous'='ENORMOUS'
(Other definitions for enormous that I've seen before include "Extraordinarily large" , "Unusually large - jumbo" , "Tremendous, gigantic" , "Vast" , "Huge, tremendous" .)