day one

noun

often capitalized D&O
: the first day or very beginning of something

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.
My first official scene on day one was with Alexis. Julia Moore, People.com, 27 May 2025 People get nervous and that’s just always been there from day one. Ali Lerman, Los Angeles Times, 27 May 2025 My first official scene on day one [on set] was with Alexis. Jackie Strause, HollywoodReporter, 26 May 2025 From day one, students learn why creating patterns for a diversity of body types is important, and the realistic statistics of consumers. Virgie Tovar, Forbes.com, 22 May 2025 See All Example Sentences for day one

Word History

First Known Use

1971, in the meaning defined above

Time Traveler
The first known use of day one was in 1971

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Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 4 Jun. 2025.

Last Updated: - Updated example sentences
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