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.
Brave new world The capital strategy underscores how these companies are building with global markets in mind from day one. Evelyn Cheng, CNBC, 4 Mar. 2026 In effect, that means companies can buy a microdrama app off the shelf with content to offer on day one. Jesse Whittock, Deadline, 4 Mar. 2026 The simple advice may seem counterintuitive in an age when young workers are being coached to build personal brands from day one and contribute constantly. Orianna Rosa Royle, Fortune, 3 Mar. 2026 The game will be available on PlayStation 5, Xbox Series X|S and PC via Steam and Epic Games Store, along with Xbox Game Pass and Nintendo Switch™2, on day one. Arushi Jacob, Variety, 3 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 9 Mar. 2026.

Last Updated: - Updated example sentences
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