streambed

[streem-bed]

noun

the channel in which a stream flows or formerly flowed.

Origin of streambed

First recorded in 1855–60; stream + bed

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for streambed

Historical Examples of streambed

Morning dawned gloomily; there was a light mist hanging over the streambed, and much of the sky was turgid with clouds.
Attrition
Jim Wannamaker