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

Compounding the challenge: traders can short-sell the stock from day one and Xiaomi won’t be considered for inclusion in benchmark MSCI gauges. Ian Mount, Fortune, "Chinese Smartphone Maker Xiaomi’s Monster IPO Flops on Its First Day of Trading," 9 July 2018 Thankfully, everything else that came with the IIsi worked great from day one, needing no repairs whatsoever. Chris Wilkinson, Ars Technica, "1990, meet 2018: How far does 20MHz of Macintosh IIsi power go today?," 1 July 2018 Interior Secretary Ryan Zinke came into office moving to expand public hunting ground from day one and issued directives last year aimed at fishing and hunting guidelines from the department. Eli Watkins, CNN, "Interior proposes allowing Alaskan hunters to bait bears, kill wolf pups," 22 May 2018 The City of Texas City has supported us from day one and their contributions have increased as the show has grown. Heidi Van Horne, Houston Chronicle, "Texas City hosts Lone Star Deluxe Hot Rod and Music Festival this weekend," 28 Apr. 2018 Through day one and into day two and day three, teams have a chance to get better this year. Dennis Manoloff,, "NFL Draft 2018: Analyst Dane Brugler chats with DMan's World (photos)," 23 Apr. 2018 He was hit on day one with a megadeal of epic proportions. Holman W. Jenkins, WSJ, "Why an Antitrust Farce Must Continue," 13 July 2018 Remember, the room doesn't have to be perfect on day one. Lisa A. Flam, Fox News, "Preparing your teen for college dorm life? Don't over-pack," 10 July 2018 Former winners have their own approach to the course on day one. Shawn Mcfarland,, "Players Look To Practice Patience At TPC River Highlands This Week," 21 June 2018

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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Statistics for day one

Last Updated

27 Aug 2018

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Time Traveler for day one

The first known use of day one was in 1971

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More Definitions for day one

day one


English Language Learners Definition of day one

: the first day or very beginning of something

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characteristic trappings or dress

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