An Etymological Dictionary of the German Language/Ruß

by Friedrich Kluge

Ruß, m., ‘soot,’ from the equiv. MidHG. and OHG. ruoȥ, m.; comp. Du. roet, ‘soot.’ LG. sot, E. soot, and its equiv. AS. sôt are scarcely allied. OHG. ruoȥ probably represents*hruoȥ,*hrôta-, but whether it is to be connected with Goth. hrôt, ‘roof,’ is more than questionable; it is more probably allied to AS. hrôt, ‘dirt.’ No cognate terms are found in the non-Teut. languages.