day one

noun

variants often Day One
Synonyms of day onenext
: 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.
Performers include Datura, the Tullamarines, Avery Cochran, Easy Honey, the Sophs, Timmy Skelly and Meek on day one. Ana Gutierrez, Austin American Statesman, 11 Mar. 2026 Listen, this is our day one at our new headquarters here in Meatpacking District of New York. Liz Hoffman, semafor.com, 10 Mar. 2026 The smarter move is building a lean, high-performing toolkit from day one. Miami Herald, 9 Mar. 2026 Washington Commanders The Commanders were busy on day one of free agency, highlighted by their work to strengthen the trenches. Sportsday Staff, Dallas Morning News, 9 Mar. 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

Browse Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 16 Mar. 2026.

Last Updated: - Updated example sentences
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