Definition of "quantity"

quantity

/ˈkwɒn.tɪ.ti/

noun
countable and uncountable, 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.
2. An indefinite amount of something.
3. A specific measured amount.
4. A considerable measure or amount.
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.
  Quotations
  For problems 58-67, translate each word phrase into an algebraic expression. […] 65. x plus 9, the quantity squared
  2006, Jerome E. Kaufmann, Karen Schwitters, Elementary and Intermediate Algebra: A Combined Approach, page 89
  The second, ( ∑ x ) 2 {\displaystyle (\sum x)^{2}} , read "summation of x, quantity squared," tells us to first add up all the xs to get ∑ x {\displaystyle \sum x} and then square ∑ x {\displaystyle \sum x} to get ( ∑ x ) 2 {\displaystyle (\sum x)^{2}} .
  2005, R. Mark Sirkin, Statistics For The Social Sciences, page 137
  ANN. r a {\displaystyle ra} quantity cubed.SERGE LANG. That's right, ( r a ) 3 {\displaystyle (ra)^{3}} .
  1985, Serge Lang, Math!: Encounters with High School Students, page 54
7. (phonology) Length of sounds.