quantify

As verbs the difference between measure and quantify

is that measure is to ascertain the quantity of a unit of material via calculated comparison with respect to a standard while quantify is to assign a quantity to.

As a noun measure

is the quantity, size, weight, distance or capacity of a substance compared to a designated standard.

As verbs the difference between quantify and overquantify

is that quantify is to assign a quantity to while overquantify is to quantify too much; to interpret with too great a focus on numbers, quotas, etc.