- (functioning as singular)
the branch of mechanics, based on the quantum theory used for interpreting the behaviour of elementary particles and atoms, which do not obey Newtonian mechanics
WordReference Random House Unabridged Dictionary of American English © 2026
quan′tum mechan′ics, [Physics.]
quan′tum-me•chan′i•cal, adj.
- Physicsa theory of the mechanics of atoms, molecules, and other physical systems that are subject to the uncertainty principle. Abbr.: QM Cf. nonrelativistic quantum mechanics, relativistic quantum mechanics.
- 1920–25
Collins Concise English Dictionary © HarperCollins Publishers::
'quantum mechanics' also found in these entries (note: many are not synonyms or translations):
Born
- Copenhagen interpretation
- Planck's constant
- Planck's radiation law
- QM
- Schrödinger equation
- classical mechanics
- correspondence principle
- de Broglie
- decoherence
- delta function
- exclusion principle
- forbidden
- matrix mechanics
- mechanics
- nonrelativistic quantum mechanics
- quantal
- quantum chemistry
- quantum field theory
- quantum jump
- quantum statistics
- quantum theory
- relativistic quantum mechanics
- uncertainty principle
- wave equation
- wave function
- wave mechanics