day one

noun

variants often Day One

: the first day or very beginning of something

Synonyms of day one

• beginning
• start
• inception
• commencement
• alpha
• onset
• launch

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 hardware and software can be ready on day one, but getting a superintendent to open an AI brief before the morning huddle is a different project entirely. — Mike Winn, Forbes.com, 29 June 2026

What can state workers expect on day one? — Kat Tran, Sacbee.com, 26 June 2026

Since day one, music has always been my artistic vehicle to amplify creativity, connection, community, collaboration, and maximum amplification of human emotion. — Jem Aswad, Variety, 25 June 2026

Ricky had all of them from day one. — Christopher Kamrani, New York Times, 25 June 2026

Word History

First Known Use

1953, in the meaning defined above

Rhymes for day one

• begun
• grandson
• gudrun
• handgun
• homespun
• outdone
• outrun
• pashtun
• redone
• rerun
• shotgun
• someone