online

American  

[on-lahyn, awn-] / ˈɒnˈlaɪn, ˈɔn- /

Or on-line,

adjective

1. operating under the direct control of, or connected to, a main computer.

2. connected by computer to one or more other computers or networks, as through a commercial electronic information service or the internet.

3. of or denoting a business that transmits electronic information over telecommunications lines.

   an online bookstore.

4. available or operating on a computer or computer network.

   an online dictionary.

5. by means of or using a computer.

   online shopping.

6. Radio. (of a network) supplying affiliated stations with all or a substantial part of their programming.

7. Television. of or relating to the final editing of a videotaped program.

8. done or accomplished while in operation or active service.

   online maintenance.

9. located on major routes or rail lines.

   online industries.

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adverb

1. with or through a computer, especially over a network.

online British  

/ ˈɒnˌlaɪn /

adjective

1. of, relating to, or concerned with a peripheral device that is directly connected to and controlled by the central processing unit of a computer

2. of or relating to the internet

   online shopping

3. occurring as part of, or involving, a continuous sequence of operations, such as a production line

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adverb

1. while connected to a computer or the internet

online Scientific  

/ ŏn′līn′ /

1. Connected to or accessible by means of a computer or computer network.

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online Cultural  

1. A term referring to locations on or use of the Internet. The term can be used to refer to a specific location or Web page (“Our sales catalogues can be found online at — ”) or to a personal activity (“I went online to find the information you wanted.”)

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Etymology

Origin of online

First recorded in 1915–20 (in sense “located on rail lines”); 1945–50 for other senses

Explanation

When you're online, you are using a computer or other device that's connected to the Internet. If someone asks if you're online, they're wondering whether you have Internet access. You might say, "I need to go online and check my email," or "I don't know if she's still meeting me — she hasn't been online all day." Or you could describe something that's available or readable on the Internet, like a news story, as being online. While the adjective officially describes a connection to any computer network, it's almost always used these days to mean "on the Internet." The word online has been around since 1950.

Example Sentences

See Examples For:

online

Some critics think a 2024 move from phone-based to online surveys by Michigan might have distorted its sentiment readings, for example.

From The Wall Street Journal ● Sep. 9, 2026

The company said sales showed "satisfactory development both in stores and online", with all its brands -- including Pull & Bear, Massimo Dutti, Bershka, Stradivarius and Oysho -- registering higher takings.

From Barron's ● Sep. 9, 2026

The online pet-supplies retailer posted a second-quarter profit of $80.5 million, or 20 cents a share, compared with $62 million, or 14 cents a share, a year earlier.

From The Wall Street Journal ● Sep. 9, 2026

Governments have stepped up an array of measures to counter the informal sector, ranging from the more repressive, such as demolition and seizure of merchandise, to supporting workers through training or moving services online.

From Barron's ● Sep. 9, 2026

Plus, I know Mom is already working on figuring out how to bring you back online.

From "A Rover's Story" by Jasmine Warga