noun (n)

• the lowest of the minor Holy Orders in the unreformed Western Church but now suppressed by the Roman Catholic Church(noun.person)

  Synonym:
  doorkeeper, ostiarius
  

  source: wordnet30
• someone who guards an entrance(noun.person)

  Synonym:
  door guard, doorkeeper, doorman, gatekeeper, hall porter, porter
  

  source: wordnet30
• The mouth of a river; an estuary.(noun)

  source: webster1913