Suitable to, or characteristic of, a master; indicating thorough knowledge or superior skill and power; showing a master's hand; as, a masterly design; a masterly performance; a masterly policy.
source: Webster 1913
adverb
With the skill of a master.
source: Webster 1913
adjective satellite
having or revealing supreme mastery or skill
A consummate artist. Consummate skill. A masterful speaker. Masterful technique. A masterly performance of the sonata. A virtuoso performance.