day one

noun

often capitalized D&O
: 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.
Nathan: Two things: First, the business model has to work from day one. Dave Knox, Forbes, 20 Feb. 2025 In fact, we were told that grocery prices would go down on day one, on January 20th. ABC News, 16 Feb. 2025 Scheffler, who started the day one shot behind Davis Thompson, matched his playing partner in Saturday’s final pairing with a 4-over 76 – the worst rounds of the day in the 54-man field. Jay Posner, San Diego Union-Tribune, 15 Feb. 2025 Donald Trump is breaking his promise to lower costs starting on day one. Josh Hammer, Newsweek, 14 Feb. 2025 See all Example Sentences for day one 

Word History

First Known Use

1971, in the meaning defined above

Time Traveler
The first known use of day one was in 1971

Dictionary Entries Near day one

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 23 Feb. 2025.

Last Updated: - Updated example sentences
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