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.
These actions empower new employees from underrepresented companies and prepare them for success from day one. Rocki Howard, Forbes, 2 Jan. 2025 The transition team and prospective Cabinet members for a second Trump administration have made clear that the goal is to hit the ground running from day one, with an extensive plan to implement on a range of issues. David Faris, Newsweek, 29 Dec. 2024 This process can help avoid surprises and provide valuable insights for both investors and the CEO on where to focus efforts to strengthen the management team from day one. Dan Hawkins, Forbes, 26 Dec. 2024 The service also gets all Xbox first-party games like Indiana Jones and The Great Circle on day one, so gamers don't need to buy them separately. Josh Hammer, Newsweek, 23 Dec. 2024 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

Dictionary Entries Near day one

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 8 Jan. 2025.

Last Updated: - Updated example sentences
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