[het-er-uh-sahy-klik, -sik-lik]

adjective Chemistry.

of or relating to the branch of chemistry dealing with cyclic compounds in which at least one of the ring members is not a carbon atom (contrasted with homocyclic).
noting such compounds, as ethylene oxide, C2H4O.

Origin of heterocyclic

First recorded in 1895–1900; hetero- + cyclic
Related formshet·er·o·cy·cle [het-er-uh-sahy-kuh l] /ˈhɛt ər əˌsaɪ kəl/, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for heterocyclic

Historical Examples of heterocyclic

British Dictionary definitions for heterocyclic



(of an organic compound) containing a closed ring of atoms, at least one of which is not a carbon atomCompare homocyclic
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

heterocyclic in Medicine


[hĕt′ə-rō-sīklĭk, -sĭklĭk]


Containing more than one kind of atom joined in a ring.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

heterocyclic in Science


[hĕt′ə-rō-sīklĭk, -sĭklĭk]

Of or relating to a compound containing a closed ring structure made of more than one kind of atom. Pyridine (C5H5N), for example, is a heterocyclic compound, as its ring contains five carbon atoms and one nitrogen atom. Compare homocyclic.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.