1. to continue to have or preserve a high level of skill, knowledge, or competence in a particular area
Pilots must maintain proficiency through regular training and practice.
Os pilotos devem manter proficiência através de treinamento e prática regular.
2. to keep one's expertise at a consistent standard over time
She maintains proficiency in three languages by studying daily.
Ela mantém proficiência em três idiomas estudando diariamente.