I have deleted the airdrop by dragging it to the trash. and empty it before I realise that! how can I get the airdrop back?

Klaus1 wrote:

By re-installing the operating system, unless you can find it in your Time Machine backup.

FWIW, AirDrop is not an app that can be deleted. I believe the user meant he deleted a file sent by AirDrop.

If you meant you deleted the AirDrop icon from the Finder Sidebar, open Finder > Preferences > Sidebar and check "AirDrop".

By re-installing the operating system, unless you can find it in your Time Machine backup.

Thanks, had forgotten that!