day one

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day one

The first day or the beginning of something. Honestly, I've loved Frank since day one, long before we officially started dating. I'm sorry, but your assistant has annoyed me from day one. How can you stand her constant cheerfulness?
See also: one

*day one

the very beginning; the very first day. (*Typically: from ~; since ~.) You haven't done anything right since day one! You're fired! She was unhappy with her new car from day one.
See also: one

day one

n. the first day. (Often with since.) You haven’t done anything right since day one! You’re fired!
See also: one
References in periodicals archive ?
Age-matched, untreated males were included as controls at days 1, 7, and 35; control animals for day 1 were also used for day 3.
The N protein could be detected as early as day 1 and until day 18.
* The Admission assessment (AA8a=01) must be completed no later than day 14 of admission, with the first day of admission counting as day 1.
A: When the Medicare A benefit kicks in on day 61, this would be considered to be day 1 of the Medicare A stay.
Immunoglobulin G antibody titer of the SARS-CoV by immunofluorescence assay was <1:25 on day 1 and 1:1,600 on day 39.
So you must complete the 14-day assessment with an ARD of day 1 through 19 to set payment for day 15 through 30.