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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adverb

  1. while connected to a computer or the internet

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
online Scientific  
/ ŏn′līn′ /
  1. Connected to or accessible by means of a computer or computer network.


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.”)


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.

Keep Reading on Vocabulary.com

Vocabulary lists containing online

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.

See Examples For:

Dan Mackta, managing director at Qobuz, an online music platform that maintains a strict human-first approach to curation, agrees the technology "is never going to want to throw a curve ball at you".

From BBC ● Oct. 24, 2026

The initiatives pitted some of California’s most successful Native American tribes with gaming interests against gambling corporations, including online sports gaming companies DraftKings and FanDuel.

From Los Angeles Times ● Oct. 24, 2026

The BBC does not know for certain whether Patel is connected to these sites, but File on 4 Investigates has established some sites are linked to an online reputation management company based in Dubai.

From BBC ● Oct. 24, 2026

The online response was brutal, with critics calling the company “AI24.”

From The Wall Street Journal ● Oct. 23, 2026

I’m sure I can find some online thing that will double as prep for next year’s curriculum, but I haven’t figured out what to look for yet.

From "Keeping Pace" by Laurie Morrison

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