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

The case claims the shop built into the PlayStation's operating system was designed to make players a "captive class".

From BBC • Mar. 10, 2026

Their Android-based operating system offers users centralised settings designed to control access to their data, with a selectable security level on a scale of one to five.

From Barron's • Mar. 4, 2026

Gen AI, in particular, will move from a co-pilot to an operating system for finance — engaging with stocks, fixed income, derivatives and other assets.

From MarketWatch • Feb. 25, 2026

“We’ve rebuilt Salesforce to become the operating system for the Agentic Enterprise, bringing humans and agents together on one trusted platform,” Benioff said.

From Barron's • Feb. 25, 2026

Dr. Z and her army of associates had only a few days left to smooth out any kinks in the library’s complex operating system.

From "Escape from Mr. Lemoncello's Library" by Chris Grabenstein