day one

noun, often capitalized D&O

Definition of day one

: the first day or very beginning of something

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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 Like Montgomery, Jackson and Ware lack the bulk to battle physically with older, stronger opponents from day one. Jon Hale, The Courier-Journal, "EJ Montgomery is entering the NBA draft. What's next for Kentucky basketball?," 15 Apr. 2020 Harold Miller, a fixture at the Oakland Coliseum from day one, died Thursday at an East Bay long-term care facility, according to his daughter, Anda. Susan Slusser,, "Oakland Coliseum fixture Harold Miller dies at 90; ‘He thought of everyone as his friend’," 3 Apr. 2020 That was baked into Tesla from day one, but for existing automakers, batteries have to become a new core competency. Jonathan M. Gitlin, Ars Technica, "As Volvo goes electric, here’s how it’s making its batteries top-notch," 31 Mar. 2020 YouTube is cracking down on political content Welcome to day one of the 2020 election. Ricki Harris, Wired, "YouTube's Disinformation Crackdown, Coronavirus Wildcards, and More News," 3 Feb. 2020 The novel coronavirus ensures that the backstage operator will be in the limelight from day one. The Economist, "A new set of eyebrows Andrew Bailey takes over as governor of the Bank of England," 15 Mar. 2020 And that’s what day one is about, is being able to meet someone. Dalton Ross,, "Ben Driebergen wants to prove he's not just a 'lucky twist guy' in Survivor: Winners at War," 3 Feb. 2020 Saxton started day one as a freshman and the team has a 17-3 record with him in the lineup in two seasons. Terry Pluto, cleveland, "Case Western Reserve football: Winning is big a relief from tests and labs for playoff-bound Spartans," 22 Nov. 2019 Thursday, the same day one of the judges rebuffed Lara’s direction to reopen a case against Applied Underwriters, the top New York state insurance regulator announced a $3 million penalty against Applied Underwriters. San Diego Union-Tribune, "State insurance commissioner accepted contributions and intervened in cases affecting donor, records show," 20 July 2019

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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First Known Use of day one

1971, in the meaning defined above

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Time Traveler for day one

Time Traveler

The first known use of day one was in 1971

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Statistics for day one

Last Updated

22 Apr 2020

Cite this Entry

“Day one.” Dictionary, Merriam-Webster, Accessed 27 May. 2020.

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day one


English Language Learners Definition of day one

: the first day or very beginning of something

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