Take off operatic heroine by the middle of the act (5)
I believe the answer is:
mimic
'take off' is the definition.
(I've seen this before)
'operatic heroine by the middle of the act' is the wordplay.
'operatic heroine' becomes 'mimi'.
'by' says to put letters next to each other.
'the middle of the act' becomes 'c' (I can't explain this - if you can you should believe this answer much more).
'mimi'+'c'='MIMIC'
Can you help me to learn more?
(Other definitions for mimic that I've seen before include "Imitate, copy appearance or mannerisms" , "Imitate satirically" , "Imitate, especially for satirical effect" , "Impersonator" , "Ape" .)