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.
The department will have solidified emergency response plans in place closer to day one of the storm. Ryanne Mena, Oc Register, 30 Dec. 2025 Keen, who was unable to have children of his own, chose to step up and help raise Genna and her three siblings, treating them as his own from day one. Ronnie Li, USA Today, 30 Dec. 2025 Ever since day one in office, I've been ranked as one of the top one or two most conservative members, either in the Texas House and the Texas Senate. Jack Fink, CBS News, 28 Dec. 2025 How To Store Leftover Prime Rib Storing your prime rib correctly is crucial to your leftovers staying as juicy and tasty as day one. Patricia S York, Southern Living, 26 Dec. 2025 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 1 Jan. 2026.

Last Updated: - Updated example sentences
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