add-on

[ad-on, -awn]

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.

adjective

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

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

add-on

noun

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

Word History and Origins

Origin of add-on¹

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

Example Sentences

"The beauty of this device is that it's completely complementary and can be an add-on to almost any sorbent material," Boriskina says.

Read more on Science Daily

Crunchyroll Manga, a new add-on for the anime streamer, will make digital manga from various publishers available to subscribers starting in early October.

Read more on Los Angeles Times

The add-on expense, sometimes referred to as a “bed tax” or “tourist tax,” can equate to hundreds of dollars in certain instances, depending on the locale and how long a guest stays.

Read more on MarketWatch

We have nothing to lose but the Evaluation and Management add-on.

Read more on The Wall Street Journal

Some have pulled their fare information from those websites to avoid paying a fee and to improve sales of add-on products such as extra legroom and frequent-flier points through their own websites.

Read more on The Wall Street Journal

Related Words

• preservative 
• supplement