the lowest point reached by a low tide.
something indicating the bottom of a decline.
the lowest or least admirable level: the low-water mark of political chicanery.
Origin of low-water mark
First recorded in 1520–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for low-water mark
Historical Examples of low-water mark
the level reached by seawater at low tide or by other stretches of water at their lowest level
the lowest point or level; nadir
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012