Vicious comeback by female? Pay no heed (7)
I believe the answer is:
dismiss
'pay no heed' is the definition.
'vicious comeback by female?' is the wordplay.
'vicious' becomes 'sid' (Sid Vicious).
'comeback' says the letters should be written backwards.
'by' says to put letters next to each other.
'female?' becomes 'miss' (miss is a kind of female**).
'sid' in reverse letter order is 'dis'.
'dis'+'miss'='DISMISS'
(Other definitions for dismiss that I've seen before include "Throw out" , "Remove from office" , "Sack - cashier" , "Fire - cashier" , "Cease to consider" .)