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Synonyms

add-on

American  
[ad-on, -awn] / ˈædˌɒn, -ˌɔn /

noun

add-ons plural
  1. a device or unit added to equipment or a construction.

    an add-on to a computer;

    a nice add-on to an old house.

  2. an extra charge.

    Add-ons for taxes and tour guide fees boosted the price of the vacation to $2,500.

  3. an additional item, as a rider or provision.

    This is just another legislative add-on.

  4. anything added on.

    Our sable faux fur vest is an easy add-on for dressy or casual occasions.


adjective

  1. being installed or provided as an add-on.

    Add-on packs for this game are just a few dollars.

add-on British  

noun

  1. a feature that can be added to a standard model or package to give increased benefits

"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

Other Word Forms

Noun Inflected Forms

Etymology

Origin of add-on

First recorded in 1945–50; noun and adj. use of verb phrase add on

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:

Kartos is due to release next year results of a late-stage clinical trial for drug candidate navtemadlin as an add-on treatment for rare blood cancer myelofibrosis, RBC says.

From The Wall Street Journal Jun. 29, 2026

The strongest stocks often provide add-on buy points during longer-term advances, and this setup may offer one above the bullish ascending triangle trigger at $500.

From Barron's May 27, 2026

If they had bought an add-on then that cost would have been covered.

From BBC May 10, 2026

Spirit grew quickly in the early 2000s, paving the way for other budget carriers such as Frontier to offer low-cost tickets with countless paid add-on options for seats and in-flight beverages.

From Los Angeles Times May 1, 2026

She lay in a supply of after-school snacks, and she gave me a key to the back door, the one that opened the add-on living room.

From "Silent To The Bone" by E.L. Konigsburg

The Brazil international joins for an initial £34m with £4m in add-ons.

From BBC Jul. 20, 2026

Trossard, who is contracted until 2027 with the Gunners, joined the club from Brighton for £21m plus add-ons in January 2023.

From BBC Jul. 14, 2026

London-listed ITV said Monday that it will receive 1.2 billion pounds in cash upon completion of the deal before additional performance related add-ons.

From The Wall Street Journal Jul. 6, 2026

For many dealers, the goal is to get shoppers in the store, where they might be willing to accept fees and add-ons after having already invested time.

From The Wall Street Journal Jun. 15, 2026

Or consider the automobile dealership: a salesman does his best to obscure the car’s base price under a mountain of add-ons and incentives.

From "Freakonomics: A Rogue Economist Explores the Hidden Side of Everything" by Steven D. Levitt

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