the GNU version of the Collaborative International Dictionary of English
ad. In a magisterial manner.
The Century Dictionary and Cyclopedia
In a magisterial manner; in the manner of a master or a magistrate; with the air of a master or the authority of a magistrate.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
ad. in an overbearingly domineering manner; as a dictator
ad. in an authoritative and magisterial manner
Word Usage
"He has been described as magisterially presiding over the younger writers, and assuming the distribution of poetical fame; but he who excels has a right to teach, and he whose judgment is incontestable, may, without usurpation, examine and decide."