noun

• A fundamental, generic term used when referring to the measurement (count, amount) of a scalar, vector, number of items or to some other way of denominating the value of a collection or group of items.
• An indefinite amount of something.
• A specific measured amount.
• A considerable measure or amount.
• (metrology) Property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as number and a reference.
• (mathematics) Indicates that the entire preceding expression is henceforth considered a single object.
• (phonology) Length of sounds.