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

observatory \observ"atory\, n.; pl. observatories. cf. f.
   observatoire.
   1. a place or building for making observations on the
      heavenly bodies.
      1913 webster

            the new observatory in greenwich park. --evelyn.
      1913 webster

   2. a building fitted with instruments for making systematic
      observations of any particular class or series of natural
      phenomena.
      1913 webster

   3. a place, as an elevated chamber, from which a view may be
      observed or commanded.
      1913 webster

   4. mil. a lookout on a flank of a battery whence an officer
      can note the range and effect of the fire; usually
      referred to as an observation post. --farrow.
      1913 webster +pjc
see also:
observatories observation post 

Observatories >> O Words
Observatories, definition of term: Observatories
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