DICTATORIAL

1. Tending to dictate; domineering.

2. Of, relating to, or characteristic of a dictator or dictatorship; autocratic.

Synonyms: These adjectives mean asserting or tending to assert one's authority or to impose one's will on others. Dictatorial stresses the highhanded, peremptory manner characteristic of a dictator: ordered the staff about in her usual dictatorial manner.
Authoritarian implies the expectation of unquestioning obedience: the timid child of authoritarian parents.
Dogmatic suggests the imposing of one's will or opinion as though these were beyond challenge: "When people are least sure, they are often most dogmatic" (John Kenneth Galbraith).
Doctrinaire implies the imposition of one's theories, beliefs, or doctrines: "They didn't know the facts . . . and I don't think it would've mattered in the slightest if they had. Very doctrinaire" (George V. Higgins).
Imperious suggests the arrogant manner of one accustomed to commanding: dismissed my opinion with an imperious gesture.
Overbearing implies a tendency to be oppressively or rudely domineering: an overbearing customer demanding to see the manager.