- 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.
- (of an organic compound) containing a closed ring of atoms, at least one of which is not a carbon atomCompare homocyclic
- Containing more than one kind of atom joined in a ring.
- 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.