Worth changing cast (5)
I believe the answer is:
throw
'cast' is the definition.
(I know that cast is a more specific form of the action the throw)
'worth changing' is the wordplay.
'changing' indicates anagramming the letters.
'worth' with letters rearranged gives 'THROW'.
(Other definitions for throw that I've seen before include "pitch or > floor" , "A turn with the dice" , "Propel through the air" , "Hurl; perplex" , "Deliberately lose" .)