slush [M17th] Slush and sludge [E17th] probably both imitate the sound made by walking through them, with slosh [E19th] being a variant of slush. Slush was also used by sailors for the accumulated fat which was left in the pot after meat was boiled for the crew. This could be sold off for use as a lubricant or fuel and the money used to buy luxuries for the crew. This was the original slush fund [M19th], which had come to mean money used as a bribe by the late 19th century.