A cent tip? Outrageous! (8)
I believe the answer is:
pittance
'a cent tip? outrageous' is the definition.
I can't judge whether this defines the answer.
'a cent tip? outrageous' is the wordplay.
'outrageous' indicates anagramming the letters (I've seen this in other clues).
'a'+'cent'+'tip'='acenttip'
'acenttip' anagrammed gives 'PITTANCE'.
(Other definitions for pittance that I've seen before include "There's very little" , "Inadequate amount of money" , "Small allowance or miserable wages" , "Miserable wage" , "very little dough" .)