yes, everyone from different place will call it differently.
Yes, if it's one cloth and one membrane, or two cloths film one film.
in order to be waterproof, geotextile must be composited with waterproof and impermeable material, once being composited, geotextile can be applied in waterproof and seepage-proof materials. the application of composite geo-membrane, composite geo-membrane plays a role of protection, geotextile is used as waterproof and seepage resistance materials, so it's called impervious geotextile or waterproof geotextile.
