Functional recovery is the process or outcome by which an entity, system, or organism regains lost or impaired capabilities or performance following disruption, damage, or loss. As a research concept and field of study, it investigates the dynamic mechanisms, pathways, metrics, and interventions associated with this restoration, focusing on observable functional outcomes and often involving adaptive or reorganizational processes. Its significance spans disciplines such as medicine, neuroscience, engineering, and ecology, informing strategies for rehabilitation, resilience, and system repair.