Words from actors: like when Caesar about to die? (6)
I believe the answer is:
asides
'words from actors' is the definition.
'like when caesar about to die?' is the wordplay.
'like' becomes 'as'.
'when caesar about to die?' becomes 'ides' (Julius Caesar was killed on the Ides of March).
'as'+'ides'='ASIDES'
(Other definitions for asides that I've seen before include "They're not heard by everybody" , "Stage whisper" , "Incidental remarks" , "throwaway comments" , "Words spoken on stage" .)