tidal flat

American  

noun

1. tideland that is flat or nearly flat and often muddy or marshy.

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tidal flat Scientific  

1. A nearly flat coastal area that is alternately covered and exposed by tides and consisting of unconsolidated sediments and precipitated salts. A tidal flat is the middle part of a tidal basin, below the vegetation-supporting salt marsh and the low-tide mark.

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Example Sentences

In the Triassic period - between about 250 and 201 million years ago - the wall was a tidal flat, which later became part of the Alpine chain.

From BBC • Dec. 16, 2025

Saemangeum developers now plan to build an airport over the last remaining tidal flat, Sura, with construction scheduled to begin in 2024.

From National Geographic • Aug. 15, 2023

The state’s Department of Enterprise Services has evaluated several options, and after a lengthy process has chosen to restore the lake to an estuary, a brackish tidal flat where the river meets the sea.

From Seattle Times • Jul. 15, 2023

In other areas of this stretch of rocks, there are sediments from an ancient tidal flat that resembles the ones these scientists traverse each day to get out here.

From Washington Post • Jul. 23, 2021

He drove through the town and down to the cliff below which his tidal flat lay.

From "Cannery Row" by John Steinbeck