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
Recent Examples on the Web
The amphibians infamously produce a number of deadly toxins, including steroidal bufadienolides and guanidinium alkaloids.
—
Andrew Paul, Popular Science, 25 Feb. 2026
Keep These Three Plants Away From Potatoes Potatoes are members of a family of vegetables called nightshades, which are rich in nutrients but also produce a toxic compound known as alkaloids.
—Heather Bien, Southern Living, 23 Feb. 2026
Enzymes in the frogs' bodies turn the alkaloids in ants, small beetles, millipedes and mites into toxins, Schwarcz wrote in an article first published in the Montreal Gazette.
—Dinah Voyles Pulver, USA Today, 15 Feb. 2026
The bitter bunch contains high levels of toxic alkaloids and must be soaked for several days to ensure safe consumption.
—Randi Gollin, Martha Stewart, 15 Feb. 2026
See All Example Sentences for alkaloid
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Andrew Paul, Popular Science, 25 Feb. 2026
Keep These Three Plants Away From Potatoes Potatoes are members of a family of vegetables called nightshades, which are rich in nutrients but also produce a toxic compound known as alkaloids.
—Heather Bien, Southern Living, 23 Feb. 2026
Enzymes in the frogs' bodies turn the alkaloids in ants, small beetles, millipedes and mites into toxins, Schwarcz wrote in an article first published in the Montreal Gazette.
—Dinah Voyles Pulver, USA Today, 15 Feb. 2026
The bitter bunch contains high levels of toxic alkaloids and must be soaked for several days to ensure safe consumption.
—Randi Gollin, Martha Stewart, 15 Feb. 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 2 Mar. 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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