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

Many of the advances Apple announced on Monday have already been rolled out to individual users by Google, with AI-powered Gemini features added to Gmail, Maps and its Android operating system for smartphones and tablets.

From Barron's • Jun. 8, 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

IBM’s own guidance suggested that 10% growth is likely the ceiling through 2026, largely due to slowing demand for its core product, the Red Hat Enterprise Linux operating system.

From Barron's • Jun. 1, 2026

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

From BBC • May 13, 2026

My brain runs on a different operating system from other people’s.

From "The London Eye Mystery" by Siobhan Dowd