sub·​sys·​tem | \ ˈsəb-ˌsi-stəm How to pronounce subsystem (audio) \
variants: or less commonly sub-system
plural subsystems also sub-systems

Definition of subsystem

: a system that is part of a larger system These subsystems of the climate system include the atmosphere, the oceans (both upper and deep oceans), the sea ice, the ice sheets, the land surface, and the biota.— Stephen H. Schneider Voyager 2 was the troublesome twin. Even before launch, failures in its onboard computer subsystems had to be rectified. The problems continued after liftoff as the attitude-control subsystem behaved in an unexpected fashion.— William I. McLaughlin

First Known Use of subsystem

1756, in the meaning defined above

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The first known use of subsystem was in 1756

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subsurface tiller



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Cite this Entry

“Subsystem.” Dictionary, Merriam-Webster, Accessed 6 Dec. 2021.

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More from Merriam-Webster on subsystem

Nglish: Translation of subsystem for Spanish Speakers


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