- Grease rubbed on the masts and running rigging or equipment as lubricant and/or preservative.
- Grease and fats from the galley.
18th century. Possibly a corruption of the word sludge.
The term “slush fund” was also derived from this, as well. It originally referred to the money raised from the sale of galley fat. The proceeds were used for luxuries for the crew.
Rogers, J.G. (1985). Origins of Sea Terms. Mystic Seaport Museum.