drop off

verb
  1. 1

    To fall asleep.

    โ€œAfter two glasses of whiskey, Tom soon dropped off in front of the television.โ€

  2. 2

    To deliver; to deposit or leave; to allow passengers to alight.

    โ€œCan you drop the kids off at school?โ€

  3. 3

    To fall.

    โ€œThe leaves were slowly dropping off the tree.โ€

  4. 4

    To lessen or reduce.

    โ€œSales have dropped off in recent months.โ€

Source: https://en.wiktionary.org/wiki/drop%20off