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.
On day one, the crew saw a lot. Emily Zemler, Condé Nast Traveler, 24 Apr. 2026 However, none of those jerseys were ever officially put into the rotation, leaving them with just a home and road uniform from day one. Ryan Morik, FOXNews.com, 23 Apr. 2026 However, that exclusivity may not have been as strong as first thought, with this group of users who talk in a private Discord group claiming to have had access since day one. James Peckham, PC Magazine, 22 Apr. 2026 New Paramount has been in the James Mangold business from day one. Nellie Andreeva, Deadline, 22 Apr. 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 26 Apr. 2026.

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