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.
In both roosts, the parrots ate both colors from day one. Amarachi Orie, CNN Money, 1 May 2026 This approach means partnering with local educational institutions, developing a robust curriculum and providing clear growth paths from day one. Mike Kelleher, Baltimore Sun, 30 Apr. 2026 Starting audience work on day one means admitting the art alone isn’t enough to fill a theater. Daren Smith, IndieWire, 29 Apr. 2026 The newest Amazon user interface, which first debuted in February, is ready from day one on this stick. James Peckham, PC Magazine, 29 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 2 May. 2026.

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