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

Add on top of that the memory supercycle, and Yang said he can see what has made “investors so excited about these stocks.”

From MarketWatch • Jan. 31, 2026

Add on £526 if you get the cheapest match tickets.

From BBC • Dec. 12, 2025

Add on top of that the AI revolution: As AI is rolled out, the labor force will almost certainly change in ways that may be less than transparent to the Fed.

From Barron's • Oct. 14, 2025

Add on top of that state budget cuts and expected reductions from the federal government, and officials and nonprofit providers say you have a perfect storm.

From Los Angeles Times • Sep. 4, 2025

Add on collection charges, ten per cent.–well, with your permission, we’ll call it two hundred flat.”

From The Missourian by Lyle, Eugene P. (Eugene Percy)

Related Words

• preservative
• supplement