ad. In a masterful manner; in an extremely confident and competent manner.
the GNU version of the Collaborative International Dictionary of English
ad. In a masterful manner; imperiously.
The Century Dictionary and Cyclopedia
In a masterful or imperious manner.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
ad. in a skillfully masterful manner; with the skill of a master
Word Usage
"What he understands and articulates masterfully is the degree to which people relate without language, simply through the way they behave to and with each other."