In general, rate is a ratio, a division, used to compare measurements. For example, a percentage (%) is a rate, which compares something to 100. In other cases, a rate can describe how often something happens. Also, it can refer to an interest rate, which is the amount of money someone has to pay to borrow money (or to be paid to lend money). In finance, there are several kinds of rates, e.g.the rate of return.