Sewage is defined as waste matter and excrement carried away in drains.(noun)
Waste matter that you flush down your toilet that gets carried away in the sewer is an example of sewage.
See sewage in Webster's New World College Dictionary
Origin: sew(er) + -age
See sewage in American Heritage Dictionary 4
Origin: Perhaps sew, sewer (from Middle English, short for Anglo-Norman sewere; see sewer1)
Origin: + -age.
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