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.
Other than leaving his teammates, Walker enjoyed what the Chiefs brought to the table during the free agency tampering period, agreeing to terms on day one. Scott Thompson, FOXNews.com, 6 May 2026 Not always a long-term career, but meaningful work that builds confidence, creates value in communities and restores structure from day one. Kaitlyn Schallhorn, Oc Register, 4 May 2026 The first few days set voting records for the state as more than 35,000 had submitted ballots by the end of day one. Irene Wright, USA Today, 4 May 2026 In both roosts, the parrots ate both colors from day one. Amarachi Orie, CNN Money, 1 May 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 10 May. 2026.

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