Weight (mass) per unit volume of a sheet of paper obtained by dividing the basis weight by the caliper (thickness).
The weight of a unit volume of powder or coating
The mass of a unit volume of powder in the loose condition, usually expressed in g/cm3.
The density of loose or compacted particulate matter determined by dividing actual weight by volume occupied; apparent density is always less than true density of a material comprising the particulate matter because volume occupied includes the space devoted to pores or cavities between particles.
The mass of a solid sample divided by a volume that it occupies in a container without applying any compaction. Apparent density is usually expressed in grams per cubic centimeter or pounds per cubic foot.