[pi-rohl, pir-ohl]

noun Chemistry.

a colorless, toxic, liquid, five-membered ring compound, C4H5N, that is a component of chlorophyll, hemin, and many other important naturally occurring substances.

Nearby words

  1. pyrrhonic,
  2. pyrrhonism,
  3. pyrrhotite,
  4. pyrrhuloxia,
  5. pyrrhus,
  6. pyrrolic,
  7. pyrrolidine,
  8. pyrrophyta,
  9. pyrrophyte,
  10. pyruvate

Origin of pyrrole

1825–35; irregular < Greek pyrr(hós) red + -ole2

Related formspyr·rol·ic [pi-rol-ik, -roh-lik] /pɪˈrɒl ɪk, -ˈroʊ lɪk/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for pyrrole

British Dictionary definitions for pyrrole



a colourless insoluble toxic liquid having a five-membered ring containing one nitrogen atom, found in many naturally occurring compounds, such as chlorophyll. Formula: C 4 H 5 NAlso called: azole
Derived Formspyrrolic (pɪˈrɒlɪk), adjective

Word Origin for pyrrole

C19: from Greek purrhos red, from pur fire + -ole 1

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

Medicine definitions for pyrrole




A five-membered heterocyclic ring compound that has an odor similar to chloroform and is the parent compound of hemoglobin, chlorophyll, and many other complex, biologically active substances.imidole
Related formspyr•rolic (pĭ-rōlĭk) adj.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for pyrrole



Any of a class of organic compounds having a five-member ring composed of four carbon atoms and one nitrogen atom. The pyrrole ring structure is a component of many biologically important compounds, including porphyrins, alkaloids, and certain amino acids.
The simplest of this class of compounds, in which a single hydrogen atom is attached to each atom in the ring. It has a pleasant odor similar to that of chloroform. Chemical formula: C4H5N.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.