1. A deposit of gravel, sand, clay, or other sediment left by a flood or glacial meltwater.
Usage: geology; archaic or technical
2. In historical geology, material deposited by the biblical Flood or by catastrophic ancient floods.
Usage: archaic; historical usage

Examples

• The diluvium layer beneath the topsoil contained fossils from the last ice age.
• Geologists examined the diluvium to understand the region's glacial history.
• The valley's diluvium deposits revealed evidence of ancient flooding.
• Early naturalists attributed diluvium formations to the biblical Deluge.
• The thick diluvium bed was composed mainly of unsorted gravel and sand.