high-water mark

American  

[hahy-waw-ter, -wot-er] / ˈhaɪˈwɔ tər, -ˈwɒt ər /

noun

1. a mark showing the highest level reached by a body of water.

2. the highest point of anything; acme.

   Her speech was the high-water mark of the conference.

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high-water mark British  

noun

1. 1. the level reached by sea water at high tide or by other stretches of water in flood

   2. the mark indicating this level

2. the highest point

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high-water mark Idioms  

1. 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]

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Etymology

Origin of high-water mark

First recorded in 1545–55

Example Sentences

Still, the CBA deal is a high-water mark for a league with a tumultuous history.

From The Wall Street Journal • Mar. 20, 2026

As for domestic policy, the high-water mark of federal government power previously was coincidently during the tenure of TR’s distant cousin, Franklin Delano Roosevelt, in the New Deal.

From Barron's • Jan. 23, 2026

The 2023 best picture field set a modern high-water mark of $4.4 billion worldwide, powered by the mega-hits “Top Gun: Maverick” and “Avatar: The Way of Water.”

From Los Angeles Times • Jan. 22, 2026

The increase in consumer prices in the 12 months ended in November could inch up to 3.1% from 3.0%, potentially the high-water mark due to tariffs.

From MarketWatch • Dec. 17, 2025

Patches of orange lichen made the only bright color, and a high-water mark on the cliff walls showed that their landing site was not at all safe.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong

Related Words

• apex
• apogee
• upper limit