In mainland Europe, a commissionaire is an attendant, messenger or subordinate employed in hotels, whose chief duty is to attend at railway stations, secure customers, take charge of their luggage, carry out the necessary formalities with respect to it and have it sent on to the hotel. They are also employed in Paris as street messengers, light porters, etc.
In the United Kingdom and some Commonwealth countries, a commissionaire may refer to a doorman, or to an employee of a Corps of Commissionaires.
text from Wikipedia, licensed under Creative Commons - Attribution - Sharealike
Racksole took upstairs with him an old commissionaire who had been attached to the outdoor service of the hôtel for many years—a grey-haired man, wiry as a terrier and strong as a mastiff.
Arnold Bennett. The Grand Babylon Hôtel (1902)
---
the door flew open, and Peterson, the commissionaire, rushed into the apartment with flushed cheeks and the face of a man who is dazed with astonishment.
Arthur Conan Doyle. The Adventures of Sherlock Holmes
---
The commissionaire who took the letter had brought her back the most cruel and unexpected answer, that there was no answer.