day one

noun

variants often Day One
Synonyms of day onenext
: 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.
My life experience and my journey as a city employee over the past decades have prepared me to serve District 7 effectively from day one. Mercury News Editorial Board, Mercury News, 29 May 2026 E-commerce companies have been dealing with this tension with shippers since day one. Jason Phillips, USA Today, 29 May 2026 From day one, success lies in building and nurturing strong relationships with the franchisor, suppliers, staff and in the community. Angelo Chavez, Forbes.com, 28 May 2026 What gets built once should run forever, like having the editor start on day one of production. Daren Smith, IndieWire, 27 May 2026 See All Example Sentences for day one

Word History

First Known Use

1953, in the meaning defined above

Time Traveler
The first known use of day one was in 1953

Browse Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 30 May. 2026.

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