septic tank

American  

[sep-tik tangk] / ˈsɛp tɪk ˌtæŋk /

noun

1. a tank, often underground, in which organic sewage is decomposed and purified by anaerobic bacteria.

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septic tank British  

noun

1. a tank, usually below ground, for containing sewage to be decomposed by anaerobic bacteria

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Etymology

Origin of septic tank

First recorded in 1900–05

Example Sentences

See Examples For:

septic tank

Decommissioning his old cesspool and buying the new septic tank already cost almost $10,000, he said, and installation and testing could easily triple that.

From Los Angeles Times ● May 15, 2026

At one point, the cave faced a potential threat when someone attempted to develop the land and convert the cave into a septic tank.

From Science Daily ● Apr. 3, 2026

Her bathroom became a toilet she fastened on top of her septic tank outside and exposed for her neighbors to see — had any of them come back.

From Los Angeles Times ● Sep. 30, 2025

The science shows the pollution problem in Lough Neagh comes largely from agriculture, with some from wastewater processing, septic tank seepage and industrial pollution around the shores.

From BBC ● Sep. 9, 2025

Her form shivered and the ghosts disappeared, leaving us alone with a pit, a Happy Flush septic tank, and a cold full moon.

From "The Battle of the Labyrinth" by Rick Riordan

Related Words

• cesspool
• sewer