Definition of red mud in English:

red mud

noun

  • 1Geology a mud of terrestrial origin, found on continental shelves and in other shallow waters, and coloured red by iron oxides.

  • 2A residue from the extraction of alumina from bauxite, coloured red by iron impurities.

Origin

Late 17th century; earliest use found in Robert Boyle (1627–1691), natural philosopher.