Quantity v. t. : To modify or qualify with respect to quantity; to fix or express the quantity of; to rate.

Quantity n. : The attribute of being so much, and not more or less; the property of being measurable, or capable of increase and decrease, multiplication and division; greatness; and more concretely, that which answers the question "How much?"; measure in regard to bulk or amount; determinate or comparative dimensions; measure; amount; bulk; extent; size.

Quantity n. : The extent or extension of a general conception, that is, the number of species or individuals to which it may be applied; also, its content or comprehension, that is, the number of its constituent qualities, attributes, or relations.

Quantity n. : The measure of a syllable; that which determines the time in which it is pronounced; as, the long or short quantity of a vowel or syllable.

Quantity n. : The relative duration of a tone.

Quantity n. : That which can be increased, diminished, or measured; especially (Math.), anything to which mathematical processes are applicable.

Quantity n. : A determinate or estimated amount; a sum or bulk; a certain portion or part; sometimes, a considerable amount; a large portion, bulk, or sum; as, a medicine taken in quantities, that is, in large quantities.

Example:
How fast in the Quantity of information on the internet increasing?

Taxonomy
quantity, magnitudes, multitude, relations, extensive quantity, ratio, intensive quantity, relationships, Aristotle, measurements, quantum, entity, quantitative structure, mass nouns, genus, apples, attributes, mathematics.

Defination from the web:
quantity is used to refer to any type of quantitative properties or attributes of things. ... A small quantity is sometimes referred to as a quantulum. ... Thus quantity is a property that exists in a range of magnitudes or multitudes. ...