English

Noun

French drain ‎(plural French drains)

1. A shallow trench, perhaps lined with tile or containing a perforated pipe, backfilled with gravel and then covered over, used to collect and channel runoff water.

References

French, Henry F., Farm Drainage: The Principles, Processes, and Effects of Draining Land with Stones, Wood, Plows, and Open Ditches and Especially with Tiles, Including Tables of Rain-Fall, Evaporation, Filtration, Excavation, Capacity of Pipes; Cost and Number to the Acre of Tiles, Etc, Etc., New York, A.O. Moore & Co., 1859.