aluminum soap

noun

: any of various aluminum salts of higher carboxylic acids (as fatty acids) including aluminum stearate and aluminum resinate that are amorphous solids insoluble in water but soluble in hydrocarbon solvents and that are used chiefly in lubricating greases, in protective coatings, and in waterproofing compositions

Word History

First Known Use

1891, in the meaning defined above

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