Synonyms for Doorkeeper (same or very similar meaning)
WordNet sense 1 (an official stationed at the entrance of a courtroom or legislative chamber):
usher
WordNet sense 2 (the lowest of the minor Holy Orders in the unreformed Western Church but now suppressed by the Roman Catholic Church):
ostiarius, ostiary
WordNet sense 3 (someone who guards an entrance):
doorman, gatekeeper, porter, door guard, hall porter
From the ODE community, based on WordNet
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