Denatonium

Part of speech: noun

Definitions

1. A bitter-tasting chemical compound added to products like antifreeze or nail-biting deterrents to discourage accidental or intentional ingestion
2. An extremely bitter substance mixed into household chemicals and medications so that people and animals are put off from swallowing them
3. A compound with an intensely unpleasant taste, used as a deterrent additive in cleaning fluids, pet products and other consumer goods

Etymology: Denatonium is a chemical name built from two pieces that come from very different corners of the language. Its first part, "denat-", is a clipping of "denature", which means to alter something so it can no longer serve its intended purpose. The word reached English from Old French "desnaturer", ultimately rooted in Latin "natura", "nature". The idea is that a substance has been changed away from its natural state, which is exactly what happens when industrial alcohol is made undrinkable. The second part, "-onium", comes from "ammonium", the name of the positively charged ion derived from ammonia. Chemists used "-onium" as a suffix for families of compounds built around that ion, so the ending signals that the molecule belongs to the quaternary ammonium group. Put together, the name tells a chemist both what the compound does and what kind of molecule it is.