check in

Definitions

General English

Aviation

  • noun
    (written as check-in)
    an airline desk where passengers register before a flight
  • verb to register by giving in your ticket, showing your passport and giving your baggage at an airline desk before a flight

Commerce

  • noun
    (written as check-in)
    a place where passengers give in their tickets for a flight
  • phrasal verb to arrive at a hotel and sign for a room
  • phrasal verb to give in your ticket to show you are ready to take the flight

Information & Library Science

  • verb to record the receipt of something

Travel

  • noun
    (written as check-in)
    the act of arriving and registering
  • verb to arrive at a hotel and write your name and address on a list
http://www.dictionarycentral.com/definition/check-in.html