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 Aurora students in the Cherry Creek School District don't start school for about nine more days, but Thursday was day one for all the new teachers embarking on their teaching journey. — Michael Abeyta, CBS News, 8 Aug. 2026 Meanwhile, Whitney and Justin Rose are the first couple who’s been on the show since day one to break up. — Jason P. Frank, Vulture, 6 Aug. 2026 Visit the school building or playground so the environment feels familiar on day one. — Ashley Lynch, Sacbee.com, 6 Aug. 2026 That is something the band, including guitarist/keyboardist Anthony Anzaldo and vocalist Ross Farrar, has never questioned since literally day one. — Brendan Menapace, SPIN, 3 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
  • Many of England’s players only arrived at their club’s pre-season camps at the beginning of August, three weeks after many sides saw the bulk of their squads return.
    — George Edwards, New York Times, 18 Aug. 2026
  • Jurors were shown a photo of a green body bag at the beginning of her questioning, followed by a grisly photo of his body.
    — CBS News, CBS News, 18 Aug. 2026
Definition of beginning
Noun
  • The Valkyries took off in the second quarter after another slow start, ending the first half on an 11-0 run on the way to a 44-28 lead at the break.
    — ABC News, ABC News, 18 Aug. 2026
  • Nolan McLean recovered from a shaky start to last six effective innings as the last-place Mets (57-69) won for the 10th time in 13 games since selling big at the trade deadline.
    — CBS New York Team, CBS News, 18 Aug. 2026
Definition of start
Noun
  • Since their inception, these wines have tasted as if something were missing beyond just alcohol—aroma, flavor, body, and balance were absent as well.
    — Mike DeSimone, Robb Report, 16 Aug. 2026
  • But Thrive has ultimately put in more than $2 billion into the ChatGPT maker since its inception.
    — Orianna Rosa Royle, Fortune, 14 Aug. 2026
Definition of inception
Noun
  • In May, college graduates entering a workforce where the technology is the primary reason for job cuts met commencement speakers hailing the AI revolution—including former Google CEO Eric Schmidt at the University of Arizona—with boos.
    — Jason Dressel, Fortune, 10 Aug. 2026
  • College students booed mentions of AI during commencement ceremonies this spring.
    — Lisa Eadicicco, CNN Money, 10 Aug. 2026
Definition of commencement
Noun
  • Warming temperatures are also expanding the range of ticks and mosquitoes that carry diseases like West Nile virus, Lyme disease, dengue, chikungunya, alpha-gal syndrome, and others.
    — Lorraine Boissoneault, STAT, 12 Aug. 2026
  • Earlier this year, astronomers with the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) created a different kind of 3D map using faint Lyman-alpha emission from hydrogen between galaxies.
    — Samantha Mathewson, Space.com, 11 Aug. 2026
Definition of alpha
Noun
  • Chan directs Zhou Xun, Wen Qi, Tian Zhuangzhuang and Wang Xiao in the drama, which centers on early-onset Alzheimer disease.
    — Naman Ramachandran, Variety, 12 Aug. 2026
  • At 51, Rabatin was a few years shy of the average age of onset, which is 55.
    — Beth Sobol, Flow Space, 12 Aug. 2026
Definition of onset
Noun
  • Further programming and launch details will be revealed closer to the October debut, the company said.
    — Naman Ramachandran, Variety, 15 Aug. 2026
  • Unlike terrestrial data centers, repairs or replacement could require another launch.
    — Contessa Brewer, CNBC, 14 Aug. 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 19 Aug. 2026.

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