›ACCOUNTINGto calculate a cost, payment, or price according to the number of hours worked, how much of something has been used, etc. in relation to a larger number of hours worked, a larger amount of something used, etc.: The bonuses for part-time employees should have been prorated based on their hours.
prorationnoun[U]›The Fund and Investment Manager may share facilities common to each, with appropriate proration of expenses between them.