narrow-minded (8)
I believe the answer is:
dogmatic
'narrow-minded' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for dogmatic that I've seen before include "I'd tog Mac out to be overbearing" , "Assertive, overbearing" , "Asserting things as incontrovertibly true" , "Giving opinions in arrogant know-all way" , "Asserting positively" .)