noun, plural: inorganic molecules
(1) A molecule not consisting of carbon atoms.
(2) Any molecule that is not considered organic, or not of biological origin.
Inorganic molecules are not usually found in living things but abound in nature or Earth. Some molecules, though, contain carbon and are still inorganic. For instance, a diamond is made up of carbon atoms yet inorganic, basically because of the early notion that an organic molecule is derived or produced by living organism, and diamond is a mineral and not of biological origin.
Word origin: inorganic + molecule.
Compare: organic molecule