day one


often capitalized D&O
: the first day or very beginning of something

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Example Sentences

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 Anyone with the word ‘first’ attached to her title will be under the microscope from day one. Ed Wittenberg, cleveland, 29 July 2022 Coming from a finance background has certainly helped us nail unit economics from day one. Rachel King, Fortune, 24 July 2022 But this iteration could turn out very differently, as it will be born under the watchful eye of Beijing from day one. Wired, 20 July 2022 But that's not how the season has gone, with the Tigers struggling nearly from day one to a bottom-five record in baseball at 37-53. Tony Garcia, Detroit Free Press, 15 July 2022 Also in the royal procession on day one were the Earl and Countess of Hopetoun, and Lady Alexandra Hooper and Mr. Tom Hooper. Emily Burack, Town & Country, 14 June 2022 What's more, all 16 zero-day hack attempts from day one were successful. Davey Winder, Forbes, 19 May 2022 Having a detailed schedule on day one is naïve at best and impossible at worst. Anthony Kinnett, National Review, 10 Mar. 2022 Our remit from day one was always to be equally distributed with respect to our capital in platform infrastructure in one bucket and content, meaning developers and publishers, in the other. Georg Szalai, The Hollywood Reporter, 7 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'day one.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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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.” Dictionary, Merriam-Webster, Accessed 19 Aug. 2022.

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Last Updated: 11 Aug 2022

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