[ pi-rohl, pir-ohl ]

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

Origin of pyrrole

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

Other words from pyrrole

  • pyr·rol·ic [pi-rol-ik, -roh-lik], /pɪˈrɒl ɪk, -ˈroʊ lɪk/, adjective

Words Nearby pyrrole Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use pyrrole in a sentence

British Dictionary definitions for pyrrole


/ (ˈpɪrəʊl, pɪˈrəʊl) /

  1. 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 N: Also called: azole

Origin of pyrrole

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

Derived forms of pyrrole

  • pyrrolic (pɪˈrɒlɪk), adjective

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

Scientific definitions for pyrrole


[ pîrōl′ ]

  1. 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.

  2. 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.

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