A one

American  

[ey wuhn] / ˈeɪ ˈwʌn /

Also A-one,

adjective

1. noting a vessel regarded by a shipping-classification society as being equipped to the highest standard and with equipment maintained in first-class condition.

2. Informal. Also A number one. first-class; excellent; superior.

   The meals there are A one.

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A-one Idioms  

1. Also, A-1; A-number-one. First-class, of the best quality, as in This is an A-one steak. The term comes from Lloyd's, the British insurance company, which in its 1775 shipping register designated the condition of a ship's hull by a letter grade (A, B, etc.) and of its cables, anchor, and other equipment by a number grade (1, 2, etc.). By the early 1800s A-1, the best possible grade, was being transferred to anything of superior quality.

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Etymology

Origin of A one

First recorded in 1830–40

Example Sentences

"That's more likely… if the strike is symbolic or a one off."

From BBC

Then we moved into a one bedroom in 2022.

From The Wall Street Journal

"If you did devolve the whole of rail infrastructure to Wales, you'd want to be really certain that all the money that you needed for that came with, I'd be very concerned whether that would happen as a one off event."

From BBC

While many of the questions were benign, including several from children, from a one reporter from Yakutia in north-eastern Siberia highlighted a tenfold increase in energy prices in the past four years.

From BBC

Farr said she doesn’t want to play grief forever but upcoming episodes will continue to show Sharon “trying to figure out who she is as a ‘one’ instead of a ‘two.’

From Los Angeles Times