quantum

 
Pronunciation: /ˈkwɒntəm/

noun (plural quanta /-tə/)

  • 1 Physics a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
  • an analogous discrete amount of any other physical quantity, such as momentum or electric charge.
  • Physiology the unit quantity of acetylcholine released at a neuromuscular junction by a single synaptic vesicle, contributing a discrete small voltage to the measured end-plate potential.
  • 2a required or allowed amount, especially an amount of money legally payable in damages: the court must determine the quantum of compensation due
  • a share or portion: each man has only a quantum of compassion

Origin:

mid 16th century (in the general sense 'quantity'): from Latin, neuter of quantus (see quantity). Sense 1 dates from the early 20th century