Organic Chemistry: the chemical science that studies molecules containing carbon atoms. Carbon is an atomic element made up of six protons, six electrons, and a variable number of neutrons and is the atom around which living matter on Earth is formed. DNA contains a large amount of carbon atoms, as do carbohydrates (sugars), lipids (fats), and proteins. Carbon is thus the molecular backbone of life.

The word “organic” is derived from the Latin which originally borrowed it from the Greek organikos, meaning “pertaining to an organ”. The phrase “organic chemistry” is attested from 1831 and was originally the study of the chemicals of living matter. More recently, the scope of this branch of chemistry was broadened to include non-living, carbon-based molecules, such as plastics.