Oxepin

Part of speech: noun

Definitions

1. A seven-membered unsaturated heterocyclic compound containing one oxygen atom in its ring, used as a parent structure in organic chemistry
2. An organic ring compound made of six carbon atoms and one oxygen atom arranged in a seven-membered unsaturated cycle
3. A cyclic chemical structure with seven ring members, one of them oxygen, forming the basis of a family of related organic compounds

Etymology: Oxepin is a chemical name, and its history is a plain piece of systematic nomenclature rather than a story about a person or a shifted meaning. It is built from "oxa-", the prefix used in chemistry to mark a ring in which one carbon atom has been replaced by oxygen, and "-epin", a stem from the heterocyclic naming system that refers to a seven-membered ring. Put together, the name describes a seven-membered ring containing one oxygen atom and a fully unsaturated set of double bonds. The word belongs to the modern vocabulary of organic chemistry, built from Greek and Latin elements in the same way as many other systematic names. Its formation follows the rules of the Hantzsch–Widman system for naming heterocycles, which chemists developed to give each ring a predictable name from its size and the atoms it contains.