ben·​ton·​ite ˈben-tə-ˌnīt How to pronounce bentonite (audio)
: an absorptive and colloidal clay used especially as a sealing agent or suspending agent (as of drugs)
bentonitic adjective

Example Sentences

Recent Examples on the Web Perfect Polish Micro-Exfoliant sloughs off dead skin cells with rice flour and tapioca starch, while the Gorgeous Glo CBD Rose Mask provides a deep pore-cleansing with rose oil and bentonite clay. Carol Lee, Discover Magazine, 29 Mar. 2021 This heat could potentially corrode the canisters, compromise the bentonite, or even crack the rock face. Howard Lee, Ars Technica, 17 Aug. 2022 There's just one catch: bentonite clay can be a moisture-zapper. Fiona Embleton, Allure, 3 Apr. 2022 The active ingredient in Blu Atlas’ revolutionary formula is bentonite - also known as volcanic ash. Grooming Playbook, The Salt Lake Tribune, 10 May 2022 Another place bentonite clay crops up is in styling products. Fiona Embleton, Allure, 3 Apr. 2022 Aztec Secret’s Indian Healing Clay is a deep-pore-cleansing mask made of 100% natural calcium bentonite clay that reviewers can’t get enough of. Kiana Murden, CNN Underscored, 31 Aug. 2020 OmniTRAX will ship in bentonite, an absorbent clay, from Wyoming. Aldo Svaldi, The Denver Post, 29 Sep. 2019 Waste will be sealed in the copper coffins, placed into the storage shafts, and surrounded by a thick layer of bentonite, a natural clay almost impermeable to water. Tim Heffernan, Popular Mechanics, 10 May 2012 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'bentonite.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Fort Benton, Montana

First Known Use

1898, in the meaning defined above

Time Traveler
The first known use of bentonite was in 1898

Dictionary Entries Near bentonite

Cite this Entry

“Bentonite.” Dictionary, Merriam-Webster, Accessed 2 Apr. 2023.

Kids Definition


ben·​ton·​ite ˈbent-ᵊn-ˌīt How to pronounce bentonite (audio)
: an absorbent clay

Medical Definition


ben·​ton·​ite ˈbent-ᵊn-ˌīt How to pronounce bentonite (audio)
: an absorptive and colloidal clay used in pharmacy especially to stabilize suspensions
bentonitic adjective

More from Merriam-Webster on bentonite

Last Updated: - Updated example sentences
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