Thiol

Part of speech: noun

Pronunciation: /ˈθaɪˌɒl/

Definitions

1. A group of organic molecules distinguished by a combination of sulfur and hydrogen at their core, resembling alcohols yet featuring sulfur's unique characteristics in their functional groups
2. Organic compounds defined by the attachment of a sulfur atom to a hydrogen atom, which play crucial roles in various biochemical processes and possess a structure akin to alcohols
3. A category of organic substances that contain a sulfhydryl group, consisting of a sulfur atom bonded to a hydrogen atom, and are analogous to alcohols in their functional structure

Etymology: Thiol is a chemical coinage built from two Greek-derived pieces. The first, "thio-", comes from the Greek "theion", meaning sulfur, which descends from an ancient Greek word for the same substance. The second, "-ol", was borrowed into chemistry from "alcohol", whose ending was adopted as a label for compounds carrying a hydroxyl-like group. So the word says, in effect, "sulfur version of an alcohol." That "-ol" has a long and surprising ancestry. "Alcohol" traces back through Medieval Latin to the Arabic "kuḥl", a fine powder used as eye cosmetic, and earlier to Aramaic and Akkadian words for the same substance. Originally, then, the root meant a powdered antimony preparation for the eyes, and only later came to name the distilled spirit and the chemical class. Thiol itself is a modern term, formed in chemistry on this pattern. It names the sulfur analogue of the alcohols, in which sulfur takes the place of oxygen in the characteristic group.