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

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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

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operating system Scientific  

/ ŏp′ə-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.

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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.

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Other Word Forms

Noun Inflected Forms

• operating systems
  plural

Etymology

Origin of operating system

First recorded in 1960–65

Example Sentences

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

From Barron's • Jul. 2, 2026

The prototype was designed to run on a proprietary operating system and integrate AI technology from SpaceX’s xAI, some of the people said.

From The Wall Street Journal • Jul. 1, 2026

It’s since made Vizio a store brand and integrated Vizio’s operating system into its existing store-brand TVs.

From The Wall Street Journal • Jun. 23, 2026

The company increasingly operates as a connected-TV advertising platform built on an operating system that sits between viewers and content providers.

From Salon • Jun. 21, 2026

It was so good, in fact, that it became—and remains—the operating system on which literally millions of computers around the world run.

From "Outliers" by Malcolm Gladwell