Definition of Ruberoid in US English:

Ruberoid

noun

US
  • A roofing material composed of felt impregnated with bitumen; any of various other building and construction materials, typically with insulating properties. [A trademark in the United Kingdom.]

Origin

Late 19th century; earliest use found in Ice & Refrigeration. From ruber, alteration of rubber + -oid. Originally a trademark in the United States, said to have been first used 1890.