follow Dictionary.com

What's the "een" in Halloween?

alkaloid

[al-kuh-loid] /ˈæl kəˌlɔɪd/
noun
1.
any of a large class of organic, nitrogen-containing ring compounds of vegetable origin and sometimes synthesized, some of which are liquid but most of which are solid, that have a bitter taste, that are usually water-insoluble and alcohol-soluble, that combine with acids without the loss of a water molecule to form water-soluble hydrochlorides, hydrobromides, or the like, and that usually exhibit pharmacological action, as nicotine, morphine, or quinine.
adjective
2.
resembling an alkali; alkaline.
Origin
1825-1835
1825-35; alkal(i) + -oid
Related forms
nonalkaloid, noun, adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source
Examples from the web for alkaloids
  • Chemical and physiological properties opium contains two main groups of alkaloids.
British Dictionary definitions for alkaloids

alkaloid

/ˈælkəˌlɔɪd/
noun
1.
any of a group of nitrogenous basic compounds found in plants, typically insoluble in water and physiologically active. Common examples are morphine, strychnine, quinine, nicotine, and caffeine
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for alkaloids

alkaloid

n.

1831, from alkali (q.v.) + -oid. "A general term applied to basic compounds of vegetable origin, bitter in taste, and having powerful effects on the animal system" [Flood]. As an adjective by 1859.

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
alkaloids in Medicine

alkaloid al·ka·loid (āl'kə-loid')
n.
Any of various organic compounds, such as nicotine and morphine, that have basic chemical properties and that usually contain at least one nitrogen atom in a heterocyclic ring.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
alkaloids in Science
alkaloid
  (āl'kə-loid')   
Any of a large class of naturally occurring, complex organic compounds that contain nitrogen and have physiological effects on animals, including humans. Most alkaloids occur in plants, although some are produced by fungi and animals. Alkaloids are bases and usually form colorless crystalline solids with a bitter taste. They have a wide range of effects and are used as medicines and poisons. Morphine, quinine, strychnine, codeine, caffeine, cocaine, and nicotine are all alkaloids.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for alkaloid

Most English speakers likely know this word

Word Value for alkaloids

14
16
Scrabble Words With Friends

Quotes with alkaloids

Nearby words for alkaloids