quantity

Etymology

From Middle English quantite, from Old French quantité, from Latin quantitās (“quantity”), from quantus (“how much”).

Pronunciation

• (UK) IPA^(key): /ˈkwɒn.tɪ.ti/

  • Audio (UK):

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• (General American) enPR: kwŏnʹ(t)ĭtē, IPA^(key): /ˈkwɑn(t)ɪti/, [ˈkʰwɑn(ɾ)ɨɾi], [ˈkʰwɑn(tʰ)ɨtʰi]

  • Audio (US):

    (file)

  • Audio (US):

    (file)

    Note: This is with a relaxed middle T, and is only used in colloquial contexts by many speakers.
• (Canada) IPA^(key): [ˈkwɑnɾəɾi]

  • Audio (Canada):

    (file)

• (obsolete) IPA^(key): /ˈkwæn.tɪ.ti/, /ˈkwæn.tɪ.tɪ/

Noun

quantity (countable and uncountable, plural quantities) (abbreviated qty)

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 cost $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, Karen Schwitters, Elementary and Intermediate Algebra: A Combined Approach, page 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, page 137:

     The second, ${\displaystyle (\sum x)^{2}}$, read "summation of x, quantity squared," tells us to first add up all the xs to get ${\displaystyle \sum x}$ and then square ${\displaystyle \sum x}$ to get ${\displaystyle (\sum x)^{2}}$.

   • 1985, Serge Lang, Math!: Encounters with High School Students, page 54:

     ANN. ${\displaystyle ra}$ quantity cubed.
     SERGE LANG. That's right, ${\displaystyle (ra)^{3}}$.

7. (phonology) Length of sounds.

Further reading

• “quantity”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.
• “quantity”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.
• “quantity”, in OneLook Dictionary Search.