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

Yubudo, South KoreaAs Byeongwoo Lee slowly walks across a sandy tidal flat on Yubudo, a small island off the west coast of South Korea, the birding guide does so quietly.

From National Geographic • Aug. 15, 2023

Today, the tidal flat is near King Street Station.

From Seattle Times • Apr. 24, 2023

The rocks indicate that area was once an estuary, where a river dumped into a tidal flat.

From Washington Post • Oct. 1, 2022

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

From "Cannery Row" by John Steinbeck