high-water mark
(hī′wôt′ər)
- the highest level reached by a body of water in tidal flow, flood, etc.
- the mark left after high water has receded
- a culminating point; highest point
See high-water mark in American Heritage Dictionary 4
noun- Abbr. HWM A mark indicating the highest level reached by a body of water.
- The highest point, as of achievement; the apex.
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