Merriam-Webster Collegiate Dictionary - masterful

 adjective  Date: 15th century  1.  a. inclined and usually competent to act as master  b. suggestive of a domineering nature  2. having or reflecting the power and skill of a master  • ~ly adverb  • ~ness noun Synonyms:  ~, domineering, imperious, peremptory, imperative mean tending to impose one's will on others. ~ implies a strong personality and ability to act authoritatively her ~ personality soon dominated the movement. domineering suggests an overbearing or arbitrary manner and an obstinate determination to enforce one's will children controlled by domineering parents. imperious implies a commanding nature or manner and often suggests arrogant assurance an imperious executive used to getting his own way. peremptory implies an abrupt dictatorial manner coupled with an unwillingness to brook disobedience or dissent given a peremptory dismissal. imperative implies peremptoriness arising more from the urgency of the situation than from an inherent will to dominate an imperative appeal for assistance. Usage:  Some commentators insist that use of ~ should be limited to sense 1 in order to preserve a distinction between it and masterly. The distinction is a modern one, excogitated by a 20th century pundit in disregard of the history of the word. Both words developed in a parallel manner but the earlier sense of masterly, equivalent to ~ 1, dropped out of use. Since masterly had but one sense, the pundit opined that it would be tidy if ~ were likewise limited to one sense and he forthwith condemned use of ~ 2 as an error. Sense 2 of ~, which is slightly older than the sense of masterly intended to replace it, has continued in reputable use all along; it cannot rationally be called an error.