Found 2 items, similar to tidemark.
English → English (WordNet) Definition: tidemark tidemark n : indicator consisting of a line at the high-water or low-water limits of the tides
English → English (gcide) Definition: Tidemark Tidemark \Tide"mark\, n. 1. a mark on a shore line indicating the normal level of the water at high tide, caused by the action of the flowing water; sometimes also used for the mark left at the point of the normal low tide; -- called also high water mark. [PJC] 2. [fig.] the maximum level which some activity has reached and from which it has declined; -- called also high water mark . [PJC]