Aldol

Part of speech: noun

Definitions

1. A chemical compound that carries both an aldehyde group and a hydroxyl alcohol group ; the beta-hydroxy aldehyde or ketone formed when two carbonyl compounds condense together
2. An organic molecule containing an aldehyde and an alcohol functional group within the same structure ; the product of a condensation reaction linking two carbonyl compounds through a hydroxyl-bearing carbon
3. A substance combining aldehyde and alcohol groups in one molecule ; a beta-hydroxy carbonyl compound produced when two aldehydes or ketones join in a base-catalyzed reaction

Etymology: Aldol is a blend, built by joining two existing chemistry words. Its first half comes from "aldehyde", itself a shortened form of "alcohol dehydrogenatum", a Latin-based name coined for the compound. The second half, "-ol", is the ending chemists attached to alcohols, so the word signals an aldehyde and an alcohol-type hydroxyl group sitting in the same molecule. The meaning follows from that structure. When two carbonyl compounds (molecules containing a carbon-oxygen double bond) join together, one can end up with a molecule that is both an aldehyde and an alcohol, and the name records exactly that combination. Chemists use the term for the resulting beta-hydroxy aldehyde or ketone, and for the reaction that forms it, which is known as the aldol reaction.