soapwort

/ˈsoʊpˌwɜrt/
noun
  1. A plant whose leaves and roots can be used to make a soapy lather when rubbed with water.
    • Hikers sometimes use soapwort as a natural soap when camping.
    • The gardener showed us how to crush soapwort leaves to create a gentle cleanser.
    • She planted soapwort near the stream because it thrives in moist soil.