mastered (Adjective) — Understood perfectly. ex. "had his algebra problems mastered"
mastered (Verb) — Be or become completely proficient or skilled in. ex. "She mastered Japanese in less than two years"
mastered (Verb) — Get on top of; deal with successfully. ex. "He mastered his shyness"
mastered (Verb) — Have dominance or the power to defeat over. ex. "Her pain completely mastered her" ex. "The methods can master the problems"
mastered (Verb) — Have a firm understanding or knowledge of; be on top of.