APY stands for Annual Percentage Yield. It is basically a fancy name for the rate of return you get on your money after accounting for compounded interest.
In a nut shell, Annual Percentage Yield tells you how much interest you will earn on a savings account during the course of a year. APY is also used to calculate interest on a loan, such as a mortgage. A higher APY is usually better when you’re looking at savings accounts, but a lower APY is best when you’re paying interest on a loan.