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addendum

noun

ə-ˈden-dəm How to pronounce addendum (audio)
Definition of addendumnext
1
as in appendix
a part added at the end of a book or periodical there's an addendum from the author to explain certain stylistic choices that she made

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Antonyms & Near Antonyms
2
as in increase
something added (as by growth) with each new addendum the list of demands simply got more absurd

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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 addendum In a company addendum to the report, which did not identify its author, Blackbird appeared to rebut those questions. — Andrew Graham, Sacbee.com, 10 Aug. 2026 Review your vehicle sales paperwork Check the purchase agreement, dealer addendum, finance documents and service records. — Kurt Knutsson, FOXNews.com, 31 July 2026 But an addendum to that was that all support for the game, short of servers being shut off, was over. — Paul Tassi, Forbes.com, 7 July 2026 During discussions about elementary and middle school social studies curriculum, board members made addendums, including education about the horrors of communism, why the Second Amendment was created and how counterculture increased the rate of divorce. — Rachel Royster, Fort Worth Star-Telegram, 27 June 2026 See All Example Sentences for addendum
Recent Examples of Synonyms for addendum
  1. appendix
  2. increase
  3. addition
  4. boost
  5. gain
Noun
  • Aside from taking antibiotics, removal of the appendix via surgery is the most common treatment.
    — Edward Segarra, USA Today, 19 Aug. 2026
  • Typically affecting those ages 10 to 30, treatment usually involves antibiotics and generally surgery to remove the appendix.
    — Clare Fisher, PEOPLE, 19 Aug. 2026
Definition of appendix
Noun
  • The penalty tax is a scale that progressively increases based on how many millions a team is over the luxury-tax threshold.
    — Hunter Patterson, New York Times, 11 Sep. 2026
  • After adjusting for demographic, lifestyle, health and environmental factors, the researchers found that any increase in light exposure above 3 lux during nighttime sleep was associated with measurable, subtle cardiac damage.
    — Barbara Mantel, NBC news, 10 Sep. 2026
Definition of increase
Noun
  • The mews, at the back of the three-acre property, is a modernist addition with 21 guestrooms, some with private terrace gardens that have just been planted.
    — Condé Nast, Condé Nast Traveler, 17 Sep. 2026
  • His Murphy is a complete 180 from that wild-eyed take on the abolitionist John Brown, not to mention a fine addition to the canon of good men who find themselves in bad company and have to navigate, pivot, and play along accordingly.
    — David Fear, Rolling Stone, 16 Sep. 2026
Definition of addition
Noun
  • Consumer spending, which accounts for about two-thirds of the US economy, has trended lower in recent months as the boost from bigger tax returns faded and higher energy costs took a bite out of people’s paychecks.
    — Bryan Mena, CNN Money, 16 Sep. 2026
  • Wadewitz added that the freight carrier may get an additional boost from its planned transcontinental merger.
    — Liz Napolitano, CNBC, 16 Sep. 2026
Definition of boost
Noun
  • Those gains, of course, allowed the club to partially circumnavigate La Liga’s spending controls so, even as the club lops off chunks of value from the asset each year, the Byzantine structure of it all has certainly served a purpose.
    — Chris Weatherspoon, New York Times, 11 Sep. 2026
  • Islamophobia helped spur the rise of populist right-wing parties in Europe, alongside the migration crisis caused by Syria’s civil war and ISIS’s territorial gains in Syria and Iraq.
    — Daniel Benjamin, Foreign Affairs, 11 Sep. 2026
Definition of gain

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addenda
addendum
adder
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Cite this Entry

“Addendum.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/addendum. Accessed 17 Sep. 2026.

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