riverbed

noun

1. The path where a river runs, or where a river once ran; the bottom earthen part of a river, not including the riverbanks.

   “Near-synonyms: streambed, creekbed”

   “The Hang En tour involves a difficult daylong trek over limestone mountain paths and along riverbeds to the remote indigenous village of Ban Doong.”

   “Detailed laser surveys carried out by Network Rail revealed that fast-flowing water on the River Eden has caused parts of the riverbed to wash away, posing a risk to the viaduct foundations.”

   “Potential signs of microbial life were found in a rock sample collected by the rover in 2024 from an ancient dry riverbed on Mars' Jezero Crater -- an area of rocky outcrops on the edges the Neretva Vallis, a river valley carved by water rushing to the canyon billions of years ago, NASA officials announced in a press conference on Wednesday.”