A mark showing the maximum water level attained or permitted in a particular body of water; especially a maximum allowable level of headwater; the water level indicated by this mark.
Origin
Mid 19th century; earliest use found in Bell's Life in London and Sporting Chronicle.
Definition of head water mark in US English:
head water mark
noun
rare
A mark showing the maximum water level attained or permitted in a particular body of water; especially a maximum allowable level of headwater; the water level indicated by this mark.
Origin
Mid 19th century; earliest use found in Bell's Life in London and Sporting Chronicle.