{adj. phr.}, {informal} Of the finest quality; superior; very good; best. * /The jeweler chose diamonds of the first water for the queen's crown./ * /The dance program at graduation was of the first water./ Compare: FIRST-CLASS.
OF THE FIRST WATER
Meaning of OF THE FIRST WATER in English
Dictionary of English idioms . Словарь английских идиом. 2012