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 top of that $800 billion in additional interest.

From Barron's • Jan. 9, 2026

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

From BBC • Dec. 12, 2025

Add on the economic uncertainty, and you get a market that’s noticeably downshifted.

From Los Angeles Times • Aug. 21, 2025

Add on the library in dots; like a railway map.

From Happy-Thought Hall by Burnand, F. C. (Francis Cowley), Sir

Related Words

• preservative
• supplement