Also found in: Dictionary, Thesaurus, Financial, Encyclopedia, Wikipedia.
1. Literally, the highest level a body of water has reached, or the mark designating such a point. Due to climate change, the high-water mark on this beach has been getting higher every year.
2. The apex, peak, or highest point of something. The high-water mark of the country's economic boom was in 2007.
The peak of something, especially an achievement. For example, This composition is the high-water mark of his entire output. This expression alludes to the highest mark left on shore by the tide. [Mid-1800s]
high-ˈwater markthe highest stage of achievement: This was the high-water mark of the ancient Greek civilization.
This refers to the highest mark left by the sea on the land or by a river when it floods.