Sediment

"The solid material that settles from a liquid; for example mud will sink and settle at the bottom of a river or stream because it is heavier than water." (Indigenous and Northern Affairs Canada, 2005) 

Sources

Indigenous and Northern Affairs Canada. "Glossary of Water Management Terms". 2005. ISBN: 0-662-41620-1. Link: https://www.aadnc-aandc.gc.ca/DAM/DAM-INTER-NU/STAGING/texte-text/wgl_1…