quantity

1. (metrology) Property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as number and a reference.countableuncountable

2. (mathematics) Indicates that the entire preceding expression is henceforth considered a single object.Examples: "x plus y quantity squared equals x squared plus 2xy plus y squared."; "For problems 58-67, translate each word phrase into an algebraic expression. […] 65. x plus 9, the quantity squared"; "The second, (#92;sumx)², read "summation of x, quantity squared," tells us to first add up all the xs to get #92;sumx and then square #92;sumx to get (#92;sumx)²."countableuncountable

3. (phonology) Length of sounds.countableuncountable