The custodian of a house, castle, prison, etc.; a warden; formerly, in France and other countries, the title of a high official who had the custody of a royal palace, fortress, etc. Obsolete exc. Historical.——牛津当代大辞典

Now, in France and other foreign countries, The person who has charge of the entrance of a building; a janitor, porter.——牛津当代大辞典

someone in a hotel whose job is to help guests by telling them about places to visit, restaurants to eat in etc.——朗文当代大辞典

someone who looks after a block of apartments and who checks who is going in and coming out, especially in France.——朗文当代大辞典  @en