carbocyclic

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Having a ring composed exclusively of carbon atoms, as benzene.

from The Century Dictionary.

• Containing a ring of carbon atoms: used especially of carbon compounds, which contain rings composed exclusively of carbon atoms, as distinguished from heterocyclic compounds, which contain rings composed of the atoms of two or more elements. Also called isocyclic compounds.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective chemistry describing a ring, all of whose atoms are carbon

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective having or relating to or characterized by a ring composed of carbon atoms