- Atom
- Atom At"om, n. [L. atomus, Gr. ?, uncut, indivisible; 'a priv.
+ ?, verbal adj. of ? to cut: cf. F. atome. See {Tome}.]
1. (Physics)
(a) An ultimate indivisible particle of matter.
(b) An ultimate particle of matter not necessarily
indivisible; a molecule.
(c) A constituent particle of matter, or a molecule
supposed to be made up of subordinate particles.
[1913 Webster]
Note: These three definitions correspond to different views of the nature of the ultimate particles of matter. In the case of the last two, the particles are more correctly called molecules. --Dana. [1913 Webster]
2. (Chem.) The smallest particle of matter that can enter into combination; one of the elementary constituents of a molecule. [1913 Webster]
3. Anything extremely small; a particle; a whit. [1913 Webster]
There was not an atom of water. --Sir J. Ross. [1913 Webster]
The Collaborative International Dictionary of English. 2000.