South German: 1. habitational name for someone from Ober- or Unter-Fall near Triberg in the Black Forest. 2. topographical name for someone living by a waterfall or the site of a landslide, from Middle High German val ‘fall’, ‘waterfall’, ‘landslide’. 3. in some cases it may derive from Falter, through assimilation of the consonants. 4. Scandinavian: unexplained.