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

Google makes the other dominant smartphone operating system, Android, and builds its own Pixel smartphones that include AI features Apple can’t yet match.

From The Wall Street Journal • Mar. 19, 2026

Its Basic programming language and DOS operating system weren’t innovative in the market—but became standards.

From Barron's • Mar. 13, 2026

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

Then he would come out of it, and the two would go out to dinner, then plunge into writing some program or into a long battle over which operating system was superior.

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