geotextile

plural geotextiles

1. Any strong, permeable fabric used in earthworks for any of a number of purposes, including separation of soil layers, filtering, reinforcing, erosion protection and protection of drainage pipes from clogging.

   The design also included geotextile lining of the trench in which the drainage pipe was buried.

   2022 March 23, Philip Haigh, “Network News: Carillion changed the design of Carmont's drains”, in RAIL, number 953, page 9

   1 more example

   You need to excavate and remove the topsoil, line the subsoil with a geotextile, then lay and compact hardcore.

   2014 August 24, Jeff Howell, “Home improvements: gravel paths and cutting heating bills [print version: Cold comfort in technology, 23 August 2014, p. P5]”, in The Daily Telegraph (Property)