Title of business admen rate poorly (5,4)
I believe the answer is:
trade name
'title of business' is the definition.
(title or name used by a business)
'admen rate poorly' is the wordplay.
'poorly' indicates anagramming the letters (a poor spelling).
'admen'+'rate'='admenrate'
'admenrate' with letters rearranged gives 'TRADE NAME'.
(Other definitions for trade name that I've seen before include "Pret A Manger?" , "commercial term?" , "Company's identifier" , "Marque, brand" , "label on product" .)