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

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

From BBC • May 10, 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

The $1 billion add-on is the latest part of CoreWeave’s strategy to tap various avenues of institutional capital.

From MarketWatch • Apr. 16, 2026

Starting April 1, a new add-on fee of $200 will be charged, up from the $149 customers paid in March, according to Cathay’s website.

From The Wall Street Journal • Apr. 1, 2026

“Two bedroom cape with add-on potential. Nu to market, builder’s special. Contemporary ranch with extras galore.”

From "Typical American" by Gish Jen

Related Words

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• supplement