ace·​to·​ni·​trile ə-ˌsē-tō-ˈnī-trəl How to pronounce acetonitrile (audio)
: the colorless liquid nitrile CH3CN of acetic acid used chiefly in organic synthesis and as a solvent

Example Sentences

Recent Examples on the Web Back then, American Cyanamid in Waggaman — now Cornerstone Chemicals — had been disposing of more than 11 million pounds of the noxious solvent acetonitrile down injection wells. Mark Schleifstein, ProPublica, 30 Oct. 2012 To identify the unique neurotoxin, the biologists cut out the venom ducts from several snails, froze them, pulverized them, and then extracted the peptides from the pulp with a mixture of water and the solvent acetonitrile. Aaron Rowe, WIRED, 11 July 2007

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

Word History


borrowed from German Acetonitril, from aceto- aceto- + Nitril nitrile

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of acetonitrile was in 1848

Dictionary Entries Near acetonitrile

Cite this Entry

“Acetonitrile.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2022.

Medical Definition



: the colorless liquid nitrile CH3CN of acetic acid usually made by dehydration of acetamide and used chiefly in organic synthesis and as a solvent

called also methyl cyanide

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