lew·​is·​ite | \ ˈlü-ə-ˌsīt \

Definition of lewisite

: a colorless or brown vesicant liquid C2H2AsCl3 developed as a poison gas for war use

Examples of lewisite in a Sentence

Recent Examples on the Web

His task was to develop poison gases—first mustard gas, then an even nastier brew called lewisite. Steven Shapin, WSJ, "Review: Citizen Conant," 27 Oct. 2017 McCaskill said the military tested the effects of mustard gas and the blister agent lewisite on about 60,000 veterans by the end of World War II. Washington Post, "McCaskill plan to help vets exposed to mustard gas passes," 3 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lewisite.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of lewisite

1895, in the meaning defined above

History and Etymology for lewisite

Winford L. Lewis †1943 American chemist

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The first known use of lewisite was in 1895

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lew·​is·​ite | \ ˈlü-ə-ˌsīt \

Medical Definition of lewisite

: a colorless or brown vesicant liquid C2H2AsCl3 developed as a poison gas for war use

More from Merriam-Webster on lewisite

Britannica.com: Encyclopedia article about lewisite

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