bag drop       
noun [ C or U ] UK uk/ˈbæɡ ˌdrɒp/ us/ˈbæɡ ˌdrɑːp/ (also mainly US baggage drop)
 (机场内已经办理好登机手续的乘客可以使用的)行李办理柜台
a place, usually at an airport, where you can leave your cases and bags to be put on a plane if you have already checked in for the flight
  At the airport customers can leave luggage at the bag drop and go straight through to security. 在机场,乘客可将行李留给行李办理柜台,然后直接通过安检。 
 - More examples
 - We stood in line for an hour for the so-called "bag drop" which wasn't functioning as a bag drop at all, but as an old-fashioned check-in.
 - The bag drop desks close strictly 40 minutes before the scheduled departure time.
 - Self-service bag drops are now available at London Heathrow.