add-on

American  

[ad-on, -awn] / ˈædˌɒn, -ˌɔn /

noun

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.

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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

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Etymology

Origin of add-on

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

Example Sentences

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

Campaign group Rail Future told the BBC it was "absolutely right that reliability and capacity increase", calling WiFi "not just an add-on or a luxury".

From BBC • May 26, 2026

Chief Executive Todd Penegor said the pizza chain is aiming to address the issue by improving its value perception and stepping up innovation to attract new customers, sell more premium pizzas and boost add-on purchases.

From The Wall Street Journal • May 7, 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

Related Words

• preservative
• supplement