day one

noun

often capitalized D&O
: 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 The set list for day one included: Sting, Matchbox Twenty, Beck, Karen Morris, Joe Wetzel, BRELAND, Ole 60, The Record Company, The Sam Bush Band, Sister Side, Lyle Lovett and more. The Courier-Journal, 23 Sep. 2024 Local infrastructure has become a key issue in the race, with Cartwright having campaigned from day one on a specific goal to revive the rail system in the area. Kyler Alvord, Peoplemag, 20 Sep. 2024 On day one the brand made $1 million–Grede and her ability to shift the denim industry through the launch of size-inclusive jeans was pivotal. Kerane Marcellus, Essence, 19 Sep. 2024 Ensure That Your Bot Passes Safety Training Much like new interns are expected to complete health and safety training on day one, chatbots must meet key safety standards. Diana Spehar, Forbes, 18 Sep. 2024 See all Example Sentences for day one 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'day one.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1971, in the meaning defined above

Time Traveler
The first known use of day one was in 1971

Dictionary Entries Near day one

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 5 Oct. 2024.

Last Updated: - Updated example sentences
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