Supporting English actors, making prediction (8)
I believe the answer is:
forecast
'prediction' is the definition.
(forecast is a kind of prediction)
'supporting english actors' is the wordplay.
'supporting' becomes 'for'.
'english' becomes 'e' (abbreviation).
'actors' becomes 'cast' (I've seen this before).
'for'+'e'+'cast'='FORECAST'
'making' is the link.
(Other definitions for forecast that I've seen before include "tip" , "Divine" , "Prophecy" , "Expect" , "Prediction, about the weather perhaps" .)