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.
To date, every court to have considered Trump's executive order banning birth right citizenship, issued on day one of his administration, has blocked it. Christina Gatti, NPR, 17 Apr. 2025 Instead, the most successful organizations weave career development into the employee experience from day one. Caroline Castrillon, Forbes.com, 17 Apr. 2025 If teams receive good news during his medical rechecks, there’s still a chance he’s selected on day one of the draft. Eddie Brown, San Diego Union-Tribune, 16 Apr. 2025 That was the plan from day one, to build Ava out a little bit more. Katie Campione, Deadline, 16 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 28 Apr. 2025.

Last Updated: - Updated example sentences
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