a specified income payable at stated intervals for a fixed or a contingent period, often for the recipient's life, in consideration of a stipulated premium paid either in prior installment payments or in a single payment.
2.
the right to receive such an income, or the duty to make such a payment or payments.
Origin: 1400–50; late Middle English < Anglo-French annuité, annualté < Medieval Latin annuitās, equivalent to Latin annu(us) yearly (derivative of annus year) + -itās-ity