Cresyl

Part of speech: noun

Definitions

1. Any of several isomeric phenolic compounds derived from coal tar, used as disinfectants and solvents in industrial chemistry
2. A class of methyl-substituted phenols obtained from coal tar and used in antiseptics, resins and chemical manufacturing
3. A toxic aromatic compound of the cresol family, employed as a disinfectant and as an intermediate in making other chemicals

Etymology: Cresyl is a chemist's building block, and its name is a neat piece of chemical naming. It is formed from "cresol" with the suffix "-yl", the standard ending chemists attach to a molecular fragment that can be carried from one compound to another. In practice, cresyl refers to the group of atoms left when a hydrogen is removed from a cresol molecule, so it is never found alone in a bottle but appears inside larger substances. The word therefore records a chain of chemical naming. Cresol is itself a family of compounds, each a methyl-substituted phenol, and the "-yl" ending marks the fragment derived from that parent. Chemists use the same pattern in words such as "ethyl" or "phenyl", which name fragments built from ethane or benzene in the same way.