- the finest quality of diamond or other precious stone
- the highest grade or best quality
WordReference Random House Unabridged Dictionary of American English © 2020
- Jewelry(formerly) the highest degree of fineness in a diamond or other precious stone. Cf. water (def. 13).
- the finest quality;
Collins Concise English Dictionary © HarperCollins Publishers::
first water n
'first water' also found in these entries: