Complex sentence: In the nomenclature of organic chemistry, a heteroatom (from Ancient Greek "heteros", different, + "atomos") is any atom that is not carbon or hydrogen, typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus or boron.
Split into simpler sentences: In the nomenclature of organic chemistry, a heteroatom (from Ancient Greek "heteros", different, + "atomos") is any atom that is not carbon or hydrogen. It is typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus or boron.