1. achieving the highest level of success or excellence in performance; showing superior results compared to others
The best-performing stocks in the portfolio gained 25% this year.
As ações de melhor desempenho na carteira ganharam 25% este ano.
2. excelling in a particular activity, task, or competition
She was the best-performing student in her class.
Ela foi a aluna de melhor desempenho na sua turma.