1. refrigeration system a cooling system for chilling or freezing
  2. ventilation system a mechanical system in a building that provides fresh air
  3. refrigeration the process of cooling or freezing for preservative purposes
  4. numeration system any notation for the representation of numbers
  5. information system system consisting of the network of all communication channels used within an organization
  6. binary numeration system a positional system of numeration that uses binary digits and a radix of two
  7. alliteration use of the same consonant at the beginning of each word
  8. ignition system the mechanism that ignites the fuel in an internal-combustion engine
  9. fuel injection system mechanical system to inject atomized fuel directly into the cylinders of an internal-combustion engine; avoids the need for a carburetor
  10. communication system a system for communicating
  11. transportation system a facility consisting of the means and equipment necessary for the movement of passengers or goods
  12. navigational system a system that provides information useful in determining the position and course of a ship or aircraft
  13. reference system a system that uses coordinates to establish position
  14. promotion system a system for advancing participants to higher-status positions
  15. refrigerant any substance used to provide cooling (as in a refrigerator)
  16. pure binary numeration system a positional system of numeration that uses binary digits and a radix of two
  17. respiratory system the system for taking in oxygen and giving off carbon dioxide; in terrestrial animals this is accomplished by breathing
  18. target acquisition system a shipboard system for the detection and identification and location of a target with enough detail to permit effective weapon employment
  19. propulsion system a system that provides a propelling or driving force
  20. air transportation system a transportation system for moving passengers or goods by air