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 Brown’s wife and kids helped out from day one and now his grandchildren and nieces and nephews help out, too, along with the community. Linda McIntosh, San Diego Union-Tribune, 18 Apr. 2024 On day one, Haldane and Case had sat upright inside the largest chamber and breathed oxygen and played the ball game at shallower depths, with both subjects developing no more than a mysterious slight cough afterward. Rachel Lance, Smithsonian Magazine, 16 Apr. 2024 The practiced Chern’s been a customer of Yesterday & Today from day one. Howard Cohen, Miami Herald, 16 Apr. 2024 That means some could be ready to go on day one, but Callender said others might need more time to ensure their facilities can handle the higher demand. Haley Bemiller, The Enquirer, 15 Apr. 2024 But the results of Wednesday’s shareholder vote, coupled with the way Disney insiders rallied around Iger in his hour of need, suggests that the next CEO hold that job will already know the route to the Rotunda executive dining room on day one. Cynthia Littleton, Variety, 3 Apr. 2024 Jameela, the first baby gorilla born by Cesarean section at the Fort Worth Zoo, has been under the constant care of Holmes and a multitude of other zoo staff since day one. Harriet Ramos, Fort Worth Star-Telegram, 22 Mar. 2024 Adobe Express users won’t see their projects from the existing mobile app in the new beta app on day one. Jess Weatherbed, The Verge, 7 Mar. 2024 Closing this gap is arguably the largest public good for which the requisite financing needs to be incorporated within AfCFTA from day one. Harry G. Broadman, Forbes, 29 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'day one.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 27 Apr. 2024.

Last Updated: - Updated example sentences
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