(1) As a verb: the act of verifying a quantity by inspection.
(2) As a vernacular noun: a seldom-used term referring to a quantifiable property or attribute of a thing. The “thing” itself can be either concrete or abstract. The usage arises from legacy System Engineering practice with respect to requirements, referring to a property being measured to determine compliance. From the perspective of abstract mathematics, that vernacular use is essentially synonymous with “parameter”.
(3) Defined herein as a noun: the collected information about how parameter values are supplied for one or more topical parameters. See Topical Parameterization, Part III: Measures.