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English definition of “mass”

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 gas mass number physics The mass number is the total number of protons and neutrons 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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