noun the relative duration of a tone.
2. quantity ·vt to modify or qualify with respect to quantity; to fix or express the quantity of; to rate.
3. quantity ·noun that which can be increased, diminished, or measured; especially (math.), anything to which mathematical processes are applicable.
4. quantity ·noun 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.
5. quantity ·noun 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.
6. quantity ·noun 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.
7. quantity ·noun 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.