Definition of sign in (or out) in English:

sign in (or out)

phrasal verb

  • Sign a register on arrival (or departure), typically in a hotel.

    ‘I signed in and took the lift to my room’
    ‘all visitors must sign out when leaving’
    • ‘Dana has just signed in., MSN informed her with a short, annoying sound effect.’
    • ‘With a goodbye both Emma and Danny got out of the car and signed in to the hotel.’
    • ‘They carry their own personal ID badges and all visitors must sign in and out of the building.’
    • ‘The clubhouse no longer has the routine where you must sign in if you are not a club member as the bar is leased out.’
    • ‘I suppose that if you didn't sign in on the council register you don't exist!’