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Definitions

operating system

[op-uh-rey-ting sis-tuhm] / ˈɒp ə reɪ tɪŋ ˌsɪs təm /
NOUN
computer software for basic operation
Synonyms
WEAK
MS-DOS MacOS OS OS/2 UNIX Windows disk operating system dos executive system software systems program

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

An Anthropic blog post said weaknesses could be found in “every major operating system and every major web browser when directed by a user to do so.”

From Barron's • Apr. 10, 2026

Apart from its serial nature and arc, the new season/series doesn’t do anything new, doesn’t attempt to update its year 2000 operating system to 2026 standards.

From Los Angeles Times • Apr. 9, 2026

The preview version of Anthropic’s new Mythos model “has already found thousands of high-severity vulnerabilities, including some in every major operating system and web browser,” the company said in a blog post.

From MarketWatch • Apr. 7, 2026

But each of those bodies still needs a brain - an operating system, or software, that tells the various bits of metal what to do.

From BBC • Apr. 7, 2026

I’d been able to coax it back to life by replacing its system memory and reloading the stone-age operating system.

From "Ready Player One: A Novel" by Ernest Cline