The status of master or ruler; control: mastery of the seas. (noun)
Full command of a subject of study: Her mastery of economic theory impressed the professors. (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "mastery" in a sentence
"Relying upon her word mastery and a senior’s susceptibility to blindly accepting comments, she plants sabotage seeds into the company airwaves:"
"And we study under world-class conductors and teachers, people whose mastery is equal to their humility and desire to serve."
"Now is the time to gain mastery over what you willingly choose to invest your attention in."