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critical mass

noun

Simple Definition of critical mass

  • : an amount of material (such as plutonium) that is large enough to allow a nuclear reaction to occur

  • : the size, number, or amount of something that is needed to cause a particular result

Source: Merriam-Webster's Learner's Dictionary

Full Definition of critical mass

  1. :  a size, number, or amount large enough to produce a particular result <the critical mass of activity needed for a retail store>

1919

First Known Use of critical mass

1919


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