1. A unified body of matter with no specific shape: a mass of clay.
2. A grouping of individual parts or elements that compose a unified body of unspecified size or quantity: "Take mankind in mass, and for the most part, they seem a mob of unnecessary duplicates" (Herman Melville).
3. A large but nonspecific amount or number: a mass of bruises.
4. A lump or aggregate of coherent material: a cancerous mass.
5. The principal part; the majority: the mass of the continent.
6. The physical volume or bulk of a solid body.
7. Abbr. m Physics A property of matter equal to the measure of the amount of matter contained in or constituting a physical body that partly determines the body's resistance to changes in the speed or direction of its motion. The mass of an object is not dependent on gravity and therefore is different from but proportional to its weight.
8. An area of unified light, shade, or color in a painting.
9. Pharmacology A thick, pasty mixture containing drugs from which pills are formed.
10. masses The body of common people or people of low socioeconomic status: "Give me your tired, your poor, / Your huddled masses yearning to breathe free" (Emma Lazarus).
tr. & intr.v. massed, mass·ing, mass·es
To gather or be gathered into a mass.
1. Of, relating to, characteristic of, directed at, or attended by a large number of people: mass education; mass communication.
2. Done or carried out on a large scale: mass production.
3. Total; complete: The mass result is impressive.
[Middle English masse, from Old French, from Latin massa, from Greek māza, maza; see mag- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.