Monochlorinate

Part of speech: verb

Definitions

1. To add a single chlorine atom to a chemical compound by replacing one hydrogen atom in its molecular structure
2. Substituting exactly one hydrogen with a chlorine atom in an organic molecule through a chemical reaction
3. Treating a compound so that it gains one chlorine atom, typically during a halogenation process in the laboratory

Etymology: "Monochlorinate" is a straightforward chemistry coinage: the prefix "mono-", from Greek "monos" meaning "single" or "alone", attached to "chlorinate", which means to introduce chlorine into a compound. Together they describe the addition of exactly one chlorine atom to a molecule, as opposed to di- (two), tri- (three) or poly- (many) chlorinations. The prefix is the same one found in "monoxide", "monomer" and "monotone", and chemists use it systematically to count atoms in a formula. The base verb "chlorinate" was itself formed in the nineteenth century from "chlorine", a word coined in 1811 by Humphry Davy from the Greek "chlōros", meaning "pale green", a reference to the gas's colour. The compound therefore combines a classical prefix with a modern chemical term built from Greek.