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.
The brand has been profitable since day one and remains debt-free. Meggen Harris, Forbes.com, 30 June 2025 The last six Tests at Headingley had been won by the side bowling first and the stats told you the pitch in Leeds now gets better and better for batting, as is shown by the last day average of 40 per wicket over the last few years, compared to a first day one of 26. Paul Newman, New York Times, 30 June 2025 Patrick Reed of Aces GC answers questions during a press conference after his round on day one of LIV Golf Dallas at Maridoe Golf Club on June 27, 2025 in Dallas, Texas. Devlina Sarkar, MSNBC Newsweek, 30 June 2025 David Beckham suited up — with his arm in a sling — for a day out at Wimbledon. Eddie Redmayne and his wife Hannah Bagshawe were in the running for most stylish pair at Wimbledon day one. Brendan Le, People.com, 30 June 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

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Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 9 Jul. 2025.

Last Updated: - Updated example sentences
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