first water

American  

noun

1. (formerly) the highest degree of fineness in a diamond or other precious stone.

2. the finest quality; highest rank.

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first water British  

noun

1. the finest quality of diamond or other precious stone

2. the highest grade or best quality

3. the most extreme kind

   a fool of the first water

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Etymology

Origin of first water

First recorded in 1745–55

Example Sentences

The return of Donald Campbell's Bluebird to the spot where the adventurer set his first water speed world record 70 years ago is "humbling", his daughter says.

From BBC • Jul. 23, 2025

The turning point came in the 1970s with the Clean Water Act, which introduced some of the first water pollution regulations.

From Slate • May 26, 2025

Tritium levels in the surrounding waters since the initial discharge have met pre-determined standards, according to tests conducted by Tepco, and no issues have been identified with the first water release, Matsumoto said.

From Reuters • Oct. 5, 2023

The ancient Egyptians invented the first water clocks and sundials more than 3,500 years ago.

From Scientific American • Apr. 25, 2023

At first, water would have to be brought from earth, and then it would have to be recycled so that it could be used over and over again.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins