A degree of aggro, certainly, for the shopkeeper (6)
I believe the answer is:
grocer
'the shopkeeper' is the definition.
(I've seen this before)
'a degree of aggro certainly' is the wordplay.
'GROCER' is hidden within the letters.
But, I am not sure how this is indicated.
'for' acts as a link.
Can you help me to learn more?
(Other definitions for grocer that I've seen before include "Retailer of food and small household goods" , "Shopkeeper who sells food and household goods" , "Seller of food and household supplies" , "Market trader" , "Retailer of foodstuffs" .)