Emphatic refusal represented in code (2,4)
I believe the answer is:
no dice
'emphatic refusal' is the definition.
(I've seen this before)
'represented in code' is the wordplay.
'represented' indicates an anagram.
'in'+'code'='incode'
'incode' is an anagram of 'NO DICE'.
(Other definitions for no dice that I've seen before include "indicates lack of success" , "Certainly not" , "Refusal (to play)" , "Shan't play!" , "with which many games are unplayable" .)