addition

noun

ə-ˈdi-shən How to pronounce addition (audio)
Definition of additionnext
1
as in extension
a smaller structure added to a main building a new addition to the library providing space for an expanded video collection

Synonyms & Similar Words

Relevance
2
as in increase
something added (as by growth) the cache of old stamps I found in the discarded desk was a huge addition to my stamp collection

Synonyms & Similar Words

Antonyms & Near Antonyms
3
as in accumulating
the act or process of becoming greater in number how do you account for the addition of more paint stains on your shirt after you put on a smock?

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of addition The venue had featured two screens and an event space until the addition of the McCall. — Jackson Murphy, IndieWire, 14 Oct. 2026 Grant’s addition to the campaign signals growing uncertainty among Republicans about the race. — Jack Harvel, Kansas City Star, 14 Oct. 2026 Surprising, quirky additions are peppered throughout, such as a small trompe l’oeil ceiling fresco of a conservatory roof, complete with climbing roses and birds. — Julia Wytrazek, TheWeek, 13 Oct. 2026 Their offense, which was supposed to be much improved with the addition of former Dolphins head coach Mike McDaniel as offensive coordinator, has been woeful. — Ryan Canfield Outkick, FOXNews.com, 13 Oct. 2026 See All Example Sentences for addition
Recent Examples of Synonyms for addition
  1. extension
  2. increase
  3. accumulating
  4. annex
  5. boost
  6. accumulation
  7. gain
Noun
  • There is a precedent — this idea is an extension of one that is already law.
    — Sarah Cannon, Fortune, 18 Oct. 2026
  • The topic of a contract extension came up during the season for the first baseman who led the team with 35 home runs.
    — LaMond Pope, Chicago Tribune, 18 Oct. 2026
Definition of extension
Noun
  • The third such increase went into effect this month, but this time there was no such rush.
    — Andrew Edgecliffe-Johnson, semafor.com, 16 Oct. 2026
  • The result is a modest but welcome increase in output, which climbs from 370 hp to 388 hp, while torque remains unchanged at 331 ft lbs.
    — Bradley Iger, Robb Report, 16 Oct. 2026
Definition of increase
Noun
  • While snow totals remain uncertain, this storm is forecast to bring colder air and has a better chance of bringing more widespread and meaningful accumulating snow, particularly in the mountains and higher elevations.
    — Alex Lehnert, CBS News, 14 Apr. 2026
Definition of accumulating
Noun
  • Just last month, classes were temporarily moved out of the basement of the Children School’s annex after officials discovered that the mitigation system wasn’t working well enough.
    — Kim Velsey, Curbed, 9 Oct. 2026
  • The Filippo Taidelli Architecture studio was located in the annex.
    — Sofia Celeste, Footwear News, 15 Sep. 2026
Definition of annex
Noun
  • Nvidia has given its frame-generation tech a boost with a new performance mode, available now in the beta release of the Nvidia app.
    — Jon Martindale, PC Magazine, 14 Oct. 2026
  • Back then, Pritzker was able to spend tens of millions to give Bailey a boost because the billionaire Democrat viewed him as an easier opponent.
    — Chris Tye, CBS News, 14 Oct. 2026
Definition of boost
Noun
  • Ice accumulation poses a serious threat to aircraft because even a thin layer can disrupt airflow over the wings, reducing lift and making a plane more difficult to control.
    — Stephen Sorace, FOXNews.com, 15 Oct. 2026
  • Researchers at Washington University found markedly different gut microbiomes in people at the earliest preclinical stages of Alzheimer’s, differences correlated with amyloid and tau accumulation before any cognitive symptoms appeared.
    — Holly Baines, STAT, 14 Oct. 2026
Definition of accumulation
Noun
  • If the answer is yes, the efficiency gain may be a competitive loss in disguise.
    — Matt Alt, Fortune, 18 Oct. 2026
  • Student test scores in the largest Sacramento-region school districts generally show a similar pattern of modest gains the recent years, but achievement levels in most cases are below the pre-pandemic scores of 2018-19.
    — Chaewon Chung October 17, Sacbee.com, 17 Oct. 2026
Definition of gain

Phrases Containing addition

Browse Nearby Words

adding up (to)
addition
additional
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Cite this Entry

“Addition.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/addition. Accessed 21 Oct. 2026.

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Britannica.com: Encyclopedia article about addition

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