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day one

noun

Definition of day onenext
as in beginning
the point at which something begins since day one of this project, we've always insisted that we would create the best product possible without any consideration of cost

Synonyms & Similar Words

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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 day one On day one in 2026, charter schools had 85,473 students enrolled and 79,633 students in attendance, down from 86,913 enrolled and 81,207 in attendance the prior academic year. — Sarah Perkel, USA Today, 2 Sep. 2026 September is living up to its infamous reputation , at least on day one. — Fred Imbert, CNBC, 1 Sep. 2026 Down payment expectations are meaningfully larger too; these programs generally want the borrower to have real equity in the deal from day one, and the strongest pricing goes to borrowers who bring more cash and better credit. — Karen Koehler, Miami Herald, 31 Aug. 2026 Tish Cyrus-Purcell Tish Cyrus has been her daughter Miley’s supporter since day one. — Bailey Bujnosek, InStyle, 28 Aug. 2026 See All Example Sentences for day one
Recent Examples of Synonyms for day one
  1. beginning
  2. start
  3. inception
  4. commencement
  5. alpha
  6. onset
  7. launch
Noun
  • The industry remains near the beginning of its cycle, and the same principles—control over keys, and the routing of decisions—apply well beyond custody, including the issuance of tokenized instruments.
    — Sergey Stopnevich, Forbes.com, 15 Sep. 2026
  • The timing of such decisions has cast a cloud of uncertainty over the sport just seven weeks out from the beginning of the regular season, and coaches involved are either fuming or biting their lips until there’s more clarity.
    — CJ Moore, New York Times, 15 Sep. 2026
Definition of beginning
Noun
  • Before last year’s 2-0 start, Taylor went 1-11 during the first two weeks of the season as a head coach.
    — Paul Dehner Jr, New York Times, 8 Sep. 2026
Definition of start
Noun
  • The selection committee has included at least one representative for each team/market since the Hall’s inception in 1963, with an increasing number of at-large selectors more recently.
    — Mike Sando, New York Times, 4 Sep. 2026
  • McKenna took over the role in 2025 from Charles Mesure, who played the former World Security Bureau boss and intelligence operative since the character's 2023 inception.
    — Taijuan Moorman, USA Today, 2 Sep. 2026
Definition of inception
Noun
  • Graduates leave Gas South Arena during Emory University's commencement ceremony in 2024.
    — Zachary Hansen, AJC.com, 3 Sep. 2026
  • Graduates at the University of Arizona and University of Central Florida booed mentions of AI during commencement speeches last spring.
    — Lisa Eadicicco, CNN Money, 2 Sep. 2026
Definition of commencement
Noun
  • Adriano Giannini plays Anna’s wealthy alpha-male businessman husband, Walter.
    — Scott Roxborough, HollywoodReporter, 7 Sep. 2026
  • Let’s hope Newcastle are not deep in the manosphere, but rather fans of the Greek alphabet — of which alpha is the first letter.
    — Eduardo Tansley, New York Times, 4 Sep. 2026
Definition of alpha
Noun
  • The groundbreaking occurred in 2018, though construction was delayed by the onset of the COVID-19 pandemic in 2020 and by subsequent supply chain issues.
    — Encyclopedia Britannica, Encyclopedia Britannica, 11 Sep. 2026
  • While researchers have made tremendous headway in diagnosing the disease early and delaying symptom onset, a cure remains elusive, and a detailed understanding of the mechanisms behind the disease still has too many gaps.
    — Mike McRae September 10, New Atlas, 10 Sep. 2026
Definition of onset
Noun
  • Firefly Aerospace announced on Wednesday a multi-launch agreement with SSC Space for two Alpha rocket launches from Sweden’s Esrange Space Center.
    — Eric Berger, ArsTechnica, 11 Sep. 2026
  • Nope, the way van den Berg is wired, nothing else made sense but a full-launch cannonball and a hope that everyone around him might notice the splash.
    — Dan Wiederer, New York Times, 11 Sep. 2026
Definition of launch

Browse Nearby Words

day nursery
day one
day ones
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Cite this Entry

“Day one.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/day%20one. Accessed 17 Sep. 2026.

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