[1] : The Collaborative International Dictionary of English v.0.48

doorkeeper \door"keep`er\, n.
   one who guards the entrance of a house or apartment; a
   porter; a janitor.
   1913 webster

[2] : WordNet (r) 2.0

doorkeeper
     n 1: an official doorkeeper as in a courtroom or legislative
          chamber syn: usher
     2: the lowest of the minor holy orders in the unreformed
        western church but now suppressed by the roman catholic
        church syn: ostiary, ostiarius
     3: someone who guards an entrance syn: doorman, door guard,
         hall porter, porter, gatekeeper, ostiary
see also:
usher ostiary ostiarius doorman door guard hall porter 
porter gatekeeper 

[3] : Moby Thesaurus II by Grady Ward, 1.0

26 moby thesaurus words for "doorkeeper":
   acolyte, acolytus, cerberus, concierge, deacon, diaconus, doorman,
   exorcist, exorcista, gatekeeper, holy orders, janitor, lector,
   major orders, minor orders, ostiarius, ostiary, porter, presbyter,
   priest, reader, receptionist, subdeacon, subdiaconus, usher,
   warden

[4] : Easton's 1897 Bible Dictionary

door-keeper
   this word is used in ps. 84:10 r.v. marg., "stand at the
   threshold of," etc., but there it signifies properly "sitting
   at the threshold in the house of god." the psalmist means that
   he would rather stand at the door of god's house and merely look
   in, than dwell in houses where iniquity prevailed.
   
     persons were appointed to keep the street door leading into
   the interior of the house john 18:16, 17; acts 12:13.
   sometimes females held this post.
   

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Doorkeeper, definition of term: Doorkeeper
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