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

This includes the little green robot that Google uses as the mascot for its Android mobile operating system.

From BBC • May 13, 2026

“They don’t care about the fact that the operating system below is blah, blah, blah.”

From The Wall Street Journal • May 2, 2026

QNX is the operating system that enables all kinds of driver assistance: collision warnings, blind-spot notifications, adaptive cruise control, pedestrian detection and steering you back into a lane when you’re drifting into trouble.

From The Wall Street Journal • May 2, 2026

Roku makes streaming devices and licenses its operating system to TV makers.

From Barron's • May 1, 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