MOLECULES
Noun
molecules
plural of molecule
Source: Wiktionary
MOLECULE
Mol"e*cule, n. Etym: [Dim. fr. L. moles a mass: cf. F. molécule. See
3d Mole.]
1. One of the very small invisible particles of which all matter is
supposed to consist.
2. (Physics)
Definition: The smallest part of any substance which possesses the
characteristic properties and qualities of that substance, and which
can exist alone in a free state.
3. (Chem.)
Definition: A group of atoms so united and combined by chemical affinity
that they form a complete, integrated whole, being the smallest
portion of any particular compound that can exist in a free state;
as, a molecule of water consists of two atoms of hydrogen and one of
oxygen. Cf. Atom.
Source: Webster’s Unabridged Dictionary 1913 Edition