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

See Examples For:

operating system

People familiar with the device described it as slimmer than an iPhone and running on a proprietary operating system.

From The Wall Street Journal ● Jul. 5, 2026

Alphabet shares fell 0.5% after the European Union’s top court upheld a $4.69 billion fine against Google in connection with its Android operating system.

From The Wall Street Journal ● Jul. 2, 2026

For much of its history, Microsoft was best known as the pioneer behind the Windows operating system and wildly popular Office software.

From Barron's ● Jun. 25, 2026

Now, with Roku’s operating system, Fox controls the discovery layer for every competitor streaming on that platform.

From Salon ● Jun. 21, 2026

I’d begun writing for a new website, Slashdot.org, an intensely geeky techno/pop-culture site devoted to the open source Linux operating system and to the open source and free software movements.

From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz