nadoknađivati

1. to make up for; to catch up on
   Vikendom nadoknađujem san koji mi fali preko nedelje. — On weekends I catch up on the sleep I miss during the week.
   Đaci subotom nadoknađuju propuštene časove. — The pupils make up missed classes on Saturdays.
2. (of costs, damage) to reimburse; to compensate
   Firma nam nadoknađuje troškove prevoza. — The company reimburses our travel expenses.

The perfective is nadoknaditi; "compensation" is nadoknada.