1.A quantity of matter cohering together so as to make one body, or an aggregation of particles or things which collectively make one body or quantity, usually of considerable size; as, a mass of ore, metal, sand, or water. "If it were not for these principles, the bodies of the earth, planets, comets, sun, and all things in them, would grow cold and freeze, and become inactive masses." "A deep mass of continual sea is slower stirred To rage."
2.(Phar.) A medicinal substance made into a cohesive, homogeneous lump, of consistency suitable for making pills; as, blue mass.
3.A large quantity; a sum. "All the mass of gold that comes into Spain." "He had spent a huge mass of treasure."
4.Bulk; magnitude; body; size. "This army of such mass and charge."
5.The principal part; the main body. "Night closed upon the pursuit, and aided the mass of the fugitives in their escape."
6.(Physics) The quantity of matter which a body contains, irrespective of its bulk or volume. Note: Mass and weight are often used, in a general way, as interchangeable terms, since the weight of a body is proportional to its mass (under the same or equal gravitative forces), and the mass is usually ascertained from the weight. Yet the two ideas, mass and weight, are quite distinct. Mass is the quantity of matter in a body; weight is the comparative force with which it tends towards the center of the earth. A mass of sugar and a mass of lead are assumed to be equal when they show an equal weight by balancing each other in the scales.
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