drop-off

noun

1. a vertical or very steep descent: The trail has a drop-off of several hundred feet.
2. a decline; decrease: Sales have shown a considerable drop-off this year.
3. a place where a person or thing can be left, received, accommodated, etc.: a new drop-off for outpatients.

adjective

4. applied when a rented vehicle is left elsewhere than at the point of hire: to pay a drop-off charge.