BLACK WASH

{ Black″ wash′ (�) or Black″wash }, n. 1. 1. (Med.) A lotion made by mixing calomel and lime water.
2. 2. A wash that blackens, as opposed to whitewash; hence, figuratively, calumny.
To remove as far as he can the modern layers of black wash, and let the man himself, fair or foul, be seen. C. Kingsley.