Noun
(organic chemistry) Any atom which is not carbon or hydrogen.
(organic chemistry) Any atom in a heterocyclic ring (or other structure normally built of carbon atoms) that is not a carbon atom.
Source: en.wiktionary.orgThe heteroatom of heterocyclic molecules is generally oxygen, sulfur, or nitrogen, with the latter being particularly common in biochemical systems. Source: Internet
Pentazole is the all nitrogen heteroatom unsaturated compound. Source: Internet
The organic ligands often bind the metal through a heteroatom such as oxygen or nitrogen, in which case such compounds are considered coordination compounds. Source: Internet
Those containing one heteroatom are, in general, stable. Source: Internet