Assert a company must employ female (6)
I believe the answer is:
affirm
'assert' is the definition.
('affirm' can be a synonym of 'assert')
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for affirm that I've seen before include "Confidently assert" , "Formally declare as true" , "Declare, assert" , "Make a formal declaration (rather than an oath)" , "State as a fact, perhaps in court" .)