A Dallas, Texas, listener wonders if his family made up the term gradoo, meaning “grime” or “schmutz.” It’s definitely more widespread than that and may derive from a French term. This is part of a complete episode.
schmutzdecke n. a naturally occurring gelatinous layer of living biological matter on a sand-based water filter, for which it provides additional filtration. Editorial Note: Occasionally spelled in English as “schmutzedecke” or...