alkaloid

noun

al·​ka·​loid ˈal-kə-ˌlȯid How to pronounce alkaloid (audio)
: any of numerous usually colorless, complex, and bitter organic bases (such as morphine or caffeine) containing nitrogen and usually oxygen that occur especially in seed plants and are typically physiologically active
alkaloidal adjective

Examples of alkaloid in a Sentence

Recent Examples on the Web Each male’s sperm is laden with the plant’s toxic chemicals, called pyrrolizidine alkaloids, which after mating spread throughout the female’s body to protect both her, and her eggs, from predators. Brian Handwerk, Smithsonian Magazine, 12 June 2024 Death camas: All parts of the death camas plant contain toxic alkaloids that can cause nausea, vomiting, diarrhea, convulsions and coma if ingested. Tiffany Acosta, The Arizona Republic, 5 June 2024 Chemical compounds in the fire ant's venom, piperidine alkaloids, cause the pustule to form over a few hours. Amanda Gardner, Health, 27 May 2024 The one common attribute of black pepper and chili pepper concerns their bioactive alkaloids, piperine in the case of black pepper and capsaicin — a constituent of chili powder and cayenne pepper — in the case of chili peppers. Joshua Siskin, Orange County Register, 20 Apr. 2024 See all Example Sentences for alkaloid 

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

Word History

First Known Use

1820, in the meaning defined above

Time Traveler
The first known use of alkaloid was in 1820

Dictionary Entries Near alkaloid

Cite this Entry

“Alkaloid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alkaloid. Accessed 7 Jul. 2024.

Medical Definition

alkaloid

noun
al·​ka·​loid ˈal-kə-ˌlȯid How to pronounce alkaloid (audio)
: any of numerous usually colorless, complex, and bitter organic bases (as morphine or caffeine) containing nitrogen and usually oxygen that occur especially in seed plants and are typically physiologically active
alkaloidal adjective

More from Merriam-Webster on alkaloid

Last Updated: - Updated example sentences
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