One who may dispense with retorts (7)
I believe the answer is:
chemist
'one who may dispense with retorts' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
This is the entire clue.
Can you help me to learn more?
(Other definitions for chemist that I've seen before include "Dispensing shop" , "Seller of medications" , "Pharmacist, apothecary" , "Drug store" , "Seller of medicines and toiletries" .)