Thienyl

Part of speech: noun, adjective

Definitions

1. Describing the univalent chemical group derived from thiophene, a sulfur-containing aromatic ring, when it attaches to another molecule
2. Referring to the monovalent radical formed by removing a hydrogen from thiophene, a five-membered ring containing one sulfur atom
3. Relating to the substituent group obtained from thiophene by stripping one hydrogen atom, commonly found in organic chemistry compounds

Etymology: Thienyl is a chemist's coinage built from "thi-", a shortened form of "thio-", meaning sulfur, and the suffix "-yl", which chemists attach to a group of atoms that stays intact through a reaction, as in ethyl or methyl. "Thio-" itself comes from the Greek "theion", meaning sulfur, and in organic chemistry it marks a sulfur atom taking the place of oxygen in a compound. Put together, thienyl names a ring-shaped group of four carbon atoms and one sulfur atom, the basic unit of the heterocyclic compound thiophene. Because the group is a radical that can be attached to other molecules, the word works as both a noun for the group and an adjective for compounds that contain it.