operating system

American  

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

noun

Computers.

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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Etymology

Origin of operating system

First recorded in 1960–65

Example Sentences

Apple deftly made the transition to Arm Macs because it controlled every part of the product: The chip, the device, the operating system, many of the apps, and the developer tools.

From Barron's • Jun. 2, 2026

There is now a version of Microsoft’s Windows operating system for Arm-based chips, and software engineers have been developing more programs for Arm as the number of Arm-based PCs grows.

From The Wall Street Journal • Jun. 2, 2026

The company’s flagship Delfi cloud operating system acts as a collaborative space where remote teams at an energy company leverage machine learning to eliminate workflow bottlenecks and significantly speed up drilling cycles.

From Barron's • May 28, 2026

The operating system stayed embedded in retail, banking, healthcare, energy, law enforcement and defense systems long after it should have been retired.

From MarketWatch • May 27, 2026

He yelled a question to Eric about the new operating system.

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