#telephone_system__telephonesystem__phone_system__phonesystem  a communication system that transmits sound between distant points
  supertype:  communication_system__communicationsystem  a system for communicating
  part:  transmission_line  central  switchboard  telephone_set
  subtype:  MEDLINE  the computer-based telephone system of the U.S. National Library of Medicine that provides rapid linkage to MEDLARS

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