Top manager ousting four (7)
I believe the answer is:
execute
'top' is the definition.
Although both the answer and definition are verbs in their base form, I cannot understand how they can define each other.
'manager ousting four' is the wordplay.
'manager' becomes 'exec' (I've seen this before).
'ousting four' becomes 'ute' (I can't explain this - if you can you should give a lot more credence to this answer).
'exec'+'ute'='EXECUTE'
Can you help me to learn more?
(Other definitions for execute that I've seen before include "Carry out, perform" , "Get it done" , "Finish off" , "Carry out; behead" , "Carry out - official killing?" .)