day one

noun

variants often Day One
Synonyms of day onenext
: the first day or very beginning of something

Synonyms of day one

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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
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.
Your future self will thank you by the end of day one. — Alesandra Dubin, Travel + Leisure, 25 June 2026 Or their hearts may convince them to close off with their day ones. — Kathleen Walsh, Vulture, 1 July 2026 What can state workers expect on day one? — Kat Tran, Sacbee.com, 26 June 2026 This World Cup has been bringing the absolute goods from day one. — Alejandro Avila Outkick, FOXNews.com, 2 July 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

Rhymes for day one

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Browse Nearby Words

day of the Lord
day one
day order
See all Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 7 Jul. 2026.

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