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Webster 1913 Edition


Quantity

Quan′ti-ty

,
Noun.
;
pl.
Quantities
(#)
.
[F.
quantite
, L.
quantitas
, fr.
quantus
bow great, how much, akin to
quam
bow, E.
how
,
who
. See
Who
.]
1.
The attribute of being so much, and not more or less; the property of being measurable, or capable of increase and decrease, multiplication and division; greatness; and more concretely, that which answers the question “How much?”; measure in regard to bulk or amount; determinate or comparative dimensions; measure; amount; bulk; extent; size.
Hence, in specific uses:
(a)
(Logic)
The extent or extension of a general conception, that is, the number of species or individuals to which it may be applied; also, its content or comprehension, that is, the number of its constituent qualities, attributes, or relations.
(b)
(Gram.)
The measure of a syllable; that which determines the time in which it is pronounced;
as, the long or short
quantity
of a vowel or syllable
.
(c)
(Mus.)
The relative duration of a tone.
2.
That which can be increased, diminished, or measured; especially
(Math.)
, anything to which mathematical processes are applicable.
☞ Quantity is discrete when it is applied to separate objects, as in number; continuous, when the parts are connected, either in succession, as in time, motion, etc., or in extension, as by the dimensions of space, viz., length, breadth, and thickness.
3.
A determinate or estimated amount; a sum or bulk; a certain portion or part; sometimes, a considerable amount; a large portion, bulk, or sum;
as, a medicine taken in
quantities
, that is, in large quantities
.
The
quantity
of extensive and curious information which he had picked up during many months of desultory, but not unprofitable, study.
Macaulay.
Quantity of estate
(Law)
,
its time of continuance, or degree of interest, as in fee, for life, or for years.
Wharton (Law Dict. )
Quantity of matter
,
in a body, its mass, as determined by its weight, or by its momentum under a given velocity.
Quantity of motion
(Mech.)
,
in a body, the relative amount of its motion, as measured by its momentum, varying as the product of mass and velocity.
Known quantities
(Math.)
,
quantities whose values are given.
Unknown quantities
(Math.)
,
quantities whose values are sought.

Webster 1828 Edition


Quantity

QUAN'TITY

,
Noun.
[L. quantitas, from quantus, how much, or as much as.]
1.
That property of any thing which may be increased or diminished.
This definition is defective, and as applicable to many other properties as to quantity. A definition strictly philosophical cannot be given. In common usage, quantity is a mass or collection of matter of indeterminate dimensions, but consisting of particles which cannot be distinguished, or which are not customarily distinguished, or which are considered in the aggregate. Thus we say, a quantity of earth, a quantity of water, a quantity of air, of light, of heat, of iron, of wood, of timber, of corn, of paper. But we do not say, a quantity of men, or of horses, or of houses; for as these are considered as separate individuals or beings, we call an assemblage of them, a number of multitude.
2.
An indefinite extent of space.
3.
A portion or part.
If I were sawed into quantities. [Not in use.]
4.
a large portion; as a medicine taken in quantities, that is, in large quantities.
5.
In mathematics, any thing which can be multiplied, divided or measured.
Thus mathematics is called the science of quantity. In algebra, quantities are known and unknown. Known quantities are usually represented by the first letters of the alphabet, as a, b, c, and unknown quantities are expressed by the last letters, x, y, z, &c. Letters thus used to represent quantities are themselves called quantities. A simple quantity is expressed by one term, as + a, or - abc; a compound is expressed by more terms than one, connected by the signs, + plus, or -minus, as a + b, or a - b + c. quantities which have the sign + prefixed, are called positive or affirmative; those which have the sign - prefixed are called negative.
6.
In grammar, the measure of a sullable; that which determines the time in which it is pronounced.
7.
In logic, a category, universal, or predicament; a general conception.
8.
In music, the relative duration of a note or syllable.
Quantity of matter, in a body, is the measure arising from the joint consideration of its magnitude and density.
Quantity of motion, in a body, is the measure arising from the joint consideration of its quantity of matter and its velocity.

Definition 2021


quantity

quantity

English

Noun

quantity (plural quantities)

  1. A fundamental, generic term used when referring to the measurement (count, amount) of a scalar, vector, number of items or to some other way of denominating the value of a collection or group of items.
    You have to choose between quantity and quality.
  2. An indefinite amount of something.
    Some soap making oils are best as base oils, used in a larger quantity in the soap, while other oils are best added in a small quantity.
    Olive oil can be used practically in any quantity.
  3. A specific measured amount.
    This bag would normally costs $497.50 for a quantity of 250, at a price of $1.99 per piece.
    Generally it should not be used in a quantity larger than 15 percent.
  4. A considerable measure or amount.
    The Boeing P-26A was the first all-metal monoplane fighter produced in quantity for the U.S. Army Air Corps.
  5. (metrology) Property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as number and a reference.
  6. (mathematics) Indicates that the entire preceding expression is henceforth considered a single object.
    x plus y quantity squared equals x squared plus 2xy plus y squared.
    • 2006, Jerome E. Kaufmann and Karen Schwitters, Elementary and Intermediate Algebra: A Combined Approach, p 89
      For problems 58-67, translate each word phrase into an algebraic expression.
      (...)
      65. x plus 9, the quantity squared
    • 2005, R. Mark Sirkin, Statistics For The Social Sciences, p137
      The second, , read "summation of x, quantity squared," tells us to first add up all the xs to get and then square to get .
    • 1985, Serge Lang, Math!: Encounters with High School Students, p54
      ANN. quantity cubed.
      SERGE LANG. That's right, .

Usage notes

  • In mathematics, used to unambiguously orate mathematical equations; it is extremely rare in print, since there is no need for it there.

Synonyms

  • Qty

Derived terms

Related terms

Translations

See also