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English definition of “mass”

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mass

noun [C]  /mæs/ us  

mass noun [C] (LARGE AMOUNT)

a large amount or number: A mass of earth and granite slid down into the narrow gorge. We had to wade through masses of seaweed.

mass noun [C] (MATTER)

[C] physics the amount of matter in any solid object or in any volume of liquid or gasmass number physics The mass number is the total number of proton s and neutron s in an atom.mass defect physics The mass defect is the difference between the mass of a nucleus (= central part of an atom) and the mass of the separate pieces that make up the nucleus.

mass noun [C] (ART)

art [U] the outside size or shape of an object, or how big it appears to be

mass

verb [I/T]  /mæs/ us  

mass verb [I/T] (CREATE LARGE AMOUNT)

to come or bring together in large numbers: [I] The crowd massed around the entrance to the exhibition.

mass

adjective [not gradable]  /mæs/ us  

mass adjective [not gradable] (LARGE AMOUNT)

involving or having an effect on a large number of people or things: weapons of mass destruction They hope the new movie will appeal to a mass audience.
(Definition of mass noun, verb, adjective from the Cambridge Academic Content Dictionary © Cambridge University Press)
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