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 The mayor before that, Bill de Blasio, had pledged to eliminate the rides on day one of his administration but abandoned the crusade after heavy opposition from unions and a media blitz involving actor Liam Neeson. — Anthony Izaguirre, Los Angeles Times, 14 Oct. 2026 On day one, about 90 percent of our customers shipped domestically only. — Arthur Zaczkiewicz, Footwear News, 13 Oct. 2026 Peter Chernin and Jesse Jacobs believed in Hello Sunshine from day one. — Jack Dunn, Variety, 13 Oct. 2026 By noon on day one, more than 3,000 ballots had already been cast. — Leondra Head, CBS News, 13 Oct. 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
  • Expect some traffic back-ups at the beginning and end of the game as parking lots empty and drivers hit the road in what is a construction zone on highways running through downtown.
    — Miami Herald Archives, Miami Herald, 20 Oct. 2026
  • Advertisement At the beginning of May, separatists turned in a petition with hundreds of thousands of signatures to push for a vote on leaving Canada, while opponents collected signatures in support of staying.
    — Chantelle Lee, Time, 20 Oct. 2026
Definition of beginning
Noun
  • After the rocky start, Saturday night seemed to be going smoother, with a new ticket system and other changes.
    — Isabel Rivera, Miami Herald, 18 Oct. 2026
  • From that inauspicious start, Yoshida built YKK, the company that today produces roughly half the world’s zippers.
    — Matt Alt, Fortune, 18 Oct. 2026
Definition of start
Noun
  • McKenzie went 17 for 28 with 295 yards and two inceptions for the Eagles (3-3, 1-2 Atlantic Coast Conference).
    — ABC News, ABC News, 17 Oct. 2026
  • Since their inception, smart glasses have struggled to erase their reputation as a privacy concern.
    — Jibin Joseph, PC Magazine, 16 Oct. 2026
Definition of inception
Noun
  • The city’s post came shortly after Butker delivered a commencement speech on May 14, 2024, at Benedictine College.
    — Jack Harvel, Kansas City Star, 2 Oct. 2026
  • The day before commencement, Metze spent the afternoon watching Texas Tech softball on TV.
    — Benjamin Wofford, New Yorker, 21 Sep. 2026
Definition of commencement
Noun
  • Perhaps most important for the team’s near future, Garland looked comfortable and confident as the Clippers’ alpha player, beginning his first full season in Los Angeles after being acquired from Cleveland in a trade for James Harden in February.
    — Joaquin Ruiz, Los Angeles Times, 22 Oct. 2026
  • The project’s decades-long timeline underscores the scope and difficulty of reimplementing an operating system from scratch, and why the project has remained in alpha for so long.
    — Nick Indge, ArsTechnica, 19 Oct. 2026
Definition of alpha
Noun
  • But in those who used it more addictively, social reward activity peaked before puberty’s onset.
    — Allison Parshall, Scientific American, 20 Oct. 2026
  • During the experiment, the chip analyzed signals to predict the onset of sawtooth instabilities, which involve rapid changes in plasma conditions.
    — Georgina Jedikovska, Interesting Engineering, 19 Oct. 2026
Definition of onset
Noun
  • Each ship comes with 16 missile launch cells, a Lockheed Martin SPY-7 radar, an anti-submarine warfare (ASW) helicopter, and other cutting-edge missile defense capabilities.
    — Christopher McFadden, Interesting Engineering, 24 Oct. 2026
  • This was the 36th launch and landing for B1063, which notably launched NASA's DART asteroid-smashing mission in November 2021.
    — Josh Dinner, Space.com, 23 Oct. 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 25 Oct. 2026.

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