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.
This approach immediately proved fruitful — on day one, Lee and Platts knocked out the instrumentals for three tracks that made it onto Pleasure, including the first two singles. Elias Leight, Billboard, 1 May 2025 The advertising frontier represents yet another example of how crypto casinos operate in regulatory gray areas, constantly adapting to reach audiences globally from day one. Boaz Sobrado, Forbes.com, 30 Apr. 2025 The clip, which has been viewed 6.7 million times, captured an unbreakable bond between siblings, and for Luke and Leo, their bond started from day one. Tom Rogers, MSNBC Newsweek, 29 Apr. 2025 There’s plenty of room for Nate to contribute from day one. Lindsay Schnell, New York Times, 28 Apr. 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 11 May. 2025.

Last Updated: - Updated example sentences
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