fixed annuity UK US noun [C] (also fixed-rate annuity) INSURANCE
► an annuity (= contract someone agrees with an insurance company to be paid an amount of money regularly) for which the payment amount remains the same for the period of the annuity: »
At the moment, most retired people who want to top up their Social Security income prefer to buy fixed-rate annuities.
Financial and business terms. 2012.