functional group

noun

1. a group of atoms responsible for the characteristic behavior of the class of compounds in which the group occurs, as the hydroxyl group in alcohols.

functional group

noun

1. chem the group of atoms in a compound, such as the hydroxyl group in an alcohol, that determines the chemical behaviour of the compound

functional group

1. An atom or group of atoms that replaces hydrogen in an organic compound. Functional groups define the structure of a family of compounds and determine its properties. The carboxyl and hydroxyl groups are functional groups that define the compounds they are part of as organic acids and alcohols, respectively.

Word History and Origins

Origin of functional group¹

First recorded in 1935–40