alkaloid

noun al·ka·loid \ ˈal-kə-ˌlȯid \

|Updated on: 1 Jul 2018

Definition of alkaloid

: 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

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alkaloidal

play \ˌal-kə-ˈlȯi-dᵊl\ adjective

Recent Examples of alkaloid from the Web

The cocaine alkaloid, the main active ingredient in coca leaves, was only isolated and synthesized as a drug in the 19th century.

— National Geographic, "How Ancient Mummies Helped This Soccer Player Get to the World Cup," 26 June 2018
That idea was reinforced in the late 1930s with the publication of a paper on the use of ergotamine tartrate, an alkaloid that was known to constrict blood vessels.

— david noonan, Scientific American, "New Nerve Drugs May Finally Prevent Migraine Headaches," 1 Dec. 2015
Sandoz scientists isolated a dozen ergot alkaloids in the hope of finding a few that might prove therapeutic.

— ellen ruppel shell, BostonGlobe.com, "Take a hit of acid and call me in the morning," 11 May 2018
The kicker is this drink’s concentration of theobromine, which is an alkaloid that acts similarly to caffeine (stimulating) but without the actual caffeine (or acidity) of coffee.

— rachelle robinett, Bon Appetit, "7 Ways to Get the Healthy, Chocolatey Goodness of Cacao into Your Diet," 27 Sep. 2017
The syllabus includes the history of medicinal plant use and cannabis chemistry, along with a lab in which students will perform plant tissue extraction for alkaloids and terpenoids and study purification procedures of different plants.

— author: amber ferguson, Alaska Dispatch News, "Finally, a degree in marijuana. But it’s not for stoners or slackers.," 23 Oct. 2017
The syllabus includes the history of medicinal plant use and cannabis chemistry, along with a lab in which students will perform plant tissue extraction for alkaloids and terpenoids and study purification procedures of different plants.

— amber ferguson, Washington Post, "Finally, a degree in marijuana: But it’s not for stoners or slackers.," 23 Oct. 2017
The first of these alkaloids, isolated by a German chemist in the early 1800s, was none other than morphine.

— maya wei-haas, Smithsonian, "The Unlikely Medical History of Chocolate Syrup," 6 Sep. 2017
Chicory’s flavor comes from alkaloids (the same plant chemical that makes caffeine taste bitter).

— christine buckley, Bon Appetit, "How to "Cleanse" Without Cutting Anything Out," 24 Aug. 2017

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

First Known Use of alkaloid

1820

in the meaning defined above

See Words from the same year

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Medical Dictionary

alkaloid

noun al·ka·loid \ ˈal-kə-ˌlȯid \

medical Definition of alkaloid

: 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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