- any theory in which matter is regarded as consisting of atoms, esp that proposed by John Dalton postulating that elements are composed of atoms that can combine in definite proportions to form compounds
- the current concept of the atom as an entity with a definite structure
See atomic structure
WordReference Random House Unabridged Dictionary of American English © 2026
atom′ic the′ory,
- Chemistry, Physics[Physics, Chem.]any of several theories describing the structure, behavior, and other properties of the atom and its component parts.
- [Philos.]atomism (def. 1).
- 1840–50
Collins Concise English Dictionary © HarperCollins Publishers::
atomic theory n
'atomic theory' also found in these entries (note: many are not synonyms or translations):