day one

noun

variants often Day One
Synonyms of day onenext
: the first day or very beginning of something

Synonyms of day one

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Examples of day one in a Sentence

We've known this about the project since Day One. since day one of this project, we've always insisted that we would create the best product possible without any consideration of cost
Recent Examples on the Web
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.
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 Leaders can distinguish between capabilities required on day one and knowledge that a capable person can reasonably acquire. — Sheila Callaham, Forbes.com, 29 Aug. 2026 Tish Cyrus-Purcell Tish Cyrus has been her daughter Miley’s supporter since day one. — Bailey Bujnosek, InStyle, 28 Aug. 2026 Private personal training One-on-one coaching built around your goals, from day one through day sixty. — Sponsored Content, Baltimore Sun, 25 Aug. 2026 See All Example Sentences for day one

Word History

First Known Use

1953, in the meaning defined above

Time Traveler
The first known use of day one was in 1953

Rhymes for day one

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Browse Nearby Words

day of the Lord
day one
day order
See all Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 1 Sep. 2026.

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