alkaloid
noun
al·ka·loid
ˈal-kə-ˌlȯid 
: 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
Examples of alkaloid in a Sentence
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This is the name for a polypeptide alkaloid that is a derivative of ergot and mimics the activity of dopamine according to CNN.
—
Gabrielle Rockson, PEOPLE, 29 May 2026
This toxic alkaloid causes severe GI problems, along with respiratory failure, central nervous system symptoms, liver and kidney damage and even death.
—Amy Deyoung, USA Today, 28 May 2026
That potential reclassification, which would not apply to the primary alkaloid in non-7-OH kratom products, is being reviewed by the Drug Enforcement Administration.
—Matthew Kelly
may 1, Kansas City Star, 1 May 2026
Daffodils contain lycorine and other alkaloids that are toxic to most mammals, including squirrels, Hardt explains.
—Madeline Buiano, Martha Stewart, 20 Apr. 2026
See All Example Sentences for alkaloid
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Gabrielle Rockson, PEOPLE, 29 May 2026
This toxic alkaloid causes severe GI problems, along with respiratory failure, central nervous system symptoms, liver and kidney damage and even death.
—Amy Deyoung, USA Today, 28 May 2026
That potential reclassification, which would not apply to the primary alkaloid in non-7-OH kratom products, is being reviewed by the Drug Enforcement Administration.
—Matthew Kelly
may 1, Kansas City Star, 1 May 2026
Daffodils contain lycorine and other alkaloids that are toxic to most mammals, including squirrels, Hardt explains.
—Madeline Buiano, Martha Stewart, 20 Apr. 2026
See All Example Sentences for alkaloid
Cite this Entry
“Alkaloid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alkaloid. Accessed 4 Jun. 2026.
Copy CitationMedical Definition
alkaloid
noun
al·ka·loid
ˈal-kə-ˌlȯid
: 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
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