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black water

American  

noun

  1. wastewater from toilets, garbage disposal, and industrial processes.


black water British  

noun

  1. household waste water that cannot be reused without purification Compare grey water

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A 2023 report showed that 8,657 outdoor toileting incidents were recorded across the Highlands that year, including 126 times where "black water" toilet waste from campervans had been dumped.

From BBC • Dec. 9, 2025

“Intensive cattle operations that are not careful about their waste had that waste spread beyond their properties, with nearby puddles of black water because of the waste,” he said.

From Los Angeles Times • Apr. 3, 2023

My eyes were burning, and black water came out of my nose whenever I showered at night.

From Seattle Times • Dec. 1, 2021

Most extinction announcements sink like a stone in black water, disappearing without making a ripple.

From Salon • Oct. 8, 2021

But a person who crossed the black water lost all caste; he was stripped of the connections that had defined him and his family for generations.

From "Sugar Changed the World: A Story of Magic, Spice, Slavery, Freedom, and Science" by Marc Aronson