bulk density

noun

: the density of a given amount of particulate matter (such as a powder)

Industry experts say the feather fiber resists wet collapse and has a greater bulk density than conventional wood pulp fiber.

—Baltimore Sun, 30 Jan. 1996

Note: The bulk density of a substance is determined by dividing the total mass of the substance by the volume that it occupies. Since the mass is in the form of a number of discrete particles, this value can vary depending on how the particles are arranged and therefore is not necessarily dependent on the physical properties of the material.

Word History

First Known Use

1940, in the meaning defined above

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