• noun the size, extent, weight, amount or number of something


  • noun an amount, especially a large amount


  • noun the amount or number of items


  • A specified number, amount, or value.
  • A large number, amount, or value.
  • For a given component, circuit, device, system, material, or the like, a property which is measurable, countable, or can otherwise be expressed as a quantity (1).
  • An entity which has a value or magnitude, upon which mathematical operations may be performed.

Origin & History of “quantity”

Latin quantus meant ‘how much’ (it was a compound adjective formed from quī ‘who’). From it was derived the noun quantitās ‘extent, amount’, which passed into English via Old French quantite. Quantum (17th c.), a noun use of the neuter form of the Latin adjective, originally denoted simply ‘amount’; its specific application to a ‘minimum amount of matter’ was introduced by Max Planck in 1900, and reinforced by Einstein in 1905.