Vesting means that an employee has earned the non-forfeitable right to employer-provided benefits (such as retirement contributions) after fulfilling certain conditions like years of service.
Official Extract:
"Vesting is the process by which employees earn rights to employer-contributed benefits over time, according to a defined schedule, as governed by ERISA requirements."
(Source: HRCI PHR Content Outline 2024–2025, Total Rewards Section, Retirement Plan Fundamentals)