check-in
/ˈtʃekɪn/noun
mass noun［often as modifier］
1- the action of reporting one's presence and registering, typically as a passenger at an airport（尤指乘客在机场的）报到; 登记：
the check-in counter.
登记柜台。
1.1
- the point at which such registration takes place报到处; 登记处。