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Synonyms

operating system

American  
[op-uh-rey-ting sis-tuhm] / ˈɒp ə reɪ tɪŋ ˌsɪs təm /

noun

Computers.
  • operating systems
    plural
  1. the collection of software that directs a computer's operations, controlling and scheduling the execution of other programs, and managing storage, input/output, and communication resources. OS


operating system British  

noun

  1. the set of software that controls the overall operation of a computer system, typically by performing such tasks as memory allocation, job scheduling, and input/output control

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

operating system Scientific  
/ ŏpə-rā′tĭng /
  1. Software designed to handle basic elements of computer operation, such as sending instructions to hardware devices like disk drives and computer screens, and allocating system resources such as memory to different software applications being run. Given uniformly designed operating systems that run on many different computers, developers of software do not need to concern themselves with these problems, and are provided with a standard platform for new programs.


operating system Cultural  
  1. The software that allows computer users to run applications with the hardware of a specific system. Microsoft® Windows® or Apple® Computer's OS are examples of operating systems.


Other Word Forms

Noun Inflected Forms

Etymology

Origin of operating system

First recorded in 1960–65

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The computing infrastructure that drives the internet, for example, mostly uses the open-source Linux operating system.

From The Wall Street Journal Aug. 11, 2026

Leo Feng, founder of Chinese agent operating system Cola.APP, said price cuts are "an inevitable trend" that "may lead to a boom in downstream applications".

From Barron's Aug. 10, 2026

Linux, a popular open-source operating system, didn’t win on license terms.

From The Wall Street Journal Aug. 6, 2026

The commission, the 27-nation bloc's antitrust regulator, had accused Google of abusing the popularity of its Android operating system to restrict competition.

From Barron's Jul. 14, 2026

Or maybe your brain works on a different operating system from other people’s like mine and you’ve worked it out too.

From "The London Eye Mystery" by Siobhan Dowd

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