Total Daily Energy Expenditure - how many calories you expend on an average day.
TDEE is Total Daily Energy Expenditure - it is how many calories you expend on an average day. It is essentially your BMR + the caloric cost of activity undertaken in a typical day. So if your typical day is fairly sedentary, BMR is pretty close to TDEE. Or, if you’re a pretty active person you may have a TDEE that is 500+ calories above your BMR. Note, though that BMR is most of TDEE.
Your TDEE is the number you should compare your caloric intake to for the purposes of controlling your weight.