- quantity or amount: the least quantum of evidence.
- a particular amount.
- a share or portion.
- a large quantity; bulk.
- Physics.
- the smallest quantity of radiant energy, equal to Planck's constant times the frequency of the associated radiation.
- the fundamental unit of a quantized physical magnitude, as angular momentum.
- sudden and significant: a quantum increase in productivity.
- physics
- the smallest quantity of some physical property, such as energy, that a system can possess according to the quantum theory
- a particle with such a unit of energy
- amount or quantity, esp a specific amount
- the least possible amount that can suffice
- something that can be quantified or measured
- loosely, sudden, spectacular, or vitally important