gua·​ni·​dine | \ ˈgwä-nə-ˌdēn How to pronounce guanidine (audio) \

Definition of guanidine

: a base CH5N3 derived from guanine that in the form of its hydrochloride acts as a parasympathetic stimulant and is used especially to denature proteins

Examples of guanidine in a Sentence

Recent Examples on the Web Using a main ingredient of sodium hydroxide, lithium hydroxide, potassium hydroxide, or guanidine hydroxide, chemical relaxers break and restructure the bonds in curly hair so that the hair becomes weaker and straight. Ashley Weatherford, The Cut, "The Everything Guide to Keratin Treatments," 15 May 2018

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

First Known Use of guanidine

circa 1864, in the meaning defined above

History and Etymology for guanidine

International Scientific Vocabulary, from guanine

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Time Traveler for guanidine

Time Traveler

The first known use of guanidine was circa 1864

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Statistics for guanidine

Cite this Entry

“Guanidine.” Dictionary, Merriam-Webster, Accessed 25 Nov. 2020.

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gua·​ni·​dine | \ ˈgwän-ə-ˌdēn How to pronounce guanidine (audio) \

Medical Definition of guanidine

: a base CH5N3 that is derived from guanine, is found especially in young tissues, and is used in organic synthesis and that in the form of its hydrochloride CH5N3·HCl is used as a drug to enhance acetylcholine activity

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