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

---

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

---

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.

---

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.

---

Etymology

Origin of operating system

First recorded in 1960–65

Example Sentences

"Legislation could cover operating system providers and others in the supply chain, such as retailers, and will not affect the use of devices owned and used by adults who verify their age," he said.

From BBC • Jun. 8, 2026

The company also said the name of its new Mac operating system will be called Golden Gate.

From The Wall Street Journal • 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

Entrata says 2.5 million units are enrolled in its operating system, but the company offers a suite of property-management services beyond RentPlus, including payment processing and rental insurance.

From MarketWatch • Jun. 2, 2026

I’d begun writing for a new website, Slashdot.org, an intensely geeky techno/pop-culture site devoted to the open source Linux operating system and to the open source and free software movements.

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