blackwash (plural blackwashes)
- (slang) (New Zealand) a whitewash victory for any New Zealand national sporting team (also known as a blackout)
- (slang) (cricket) a whitewash victory for the West Indies cricket team
- (medicine) A lotion made by mixing calomel and limewater.
- (slang, mining) public campaigns and advertising funded by the coal industry to draw attention away from environmentally unsustainable practices or to justify exclusion from carbon taxes.