A technique for reproducing a texture or relief design by laying paper over it and rubbing it with a drawing medium, such as pencil, charcoal or crayon. Max Ernst (1891-1976) and other Surrealist artists incorporated frottage in their work. Pronunciation here. Video here.
Max Ernst. The Start of the Chestnut Tree. Frottage with pencil and gouache. 1925. The Morgan Library and Museum, New York.