composting toilet

noun

plural composting toilets
: a self-contained waterless toilet having a lower composting compartment where human waste is typically mixed with a carbon-rich bulking agent (such as sawdust or peat moss) and undergoes aerobic decomposition (as by bacteria)

Word History

First Known Use

1972, in the meaning defined above

Time Traveler
The first known use of composting toilet was in 1972

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Cite this Entry

“Composting toilet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/composting%20toilet. Accessed 29 Aug. 2026.

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