the amount by which the mass of an atomic nucleus differs from the sum of the masses of its constituent particles, being the mass equivalent of the energy released in the formation of the nucleus.
Compare binding energy.
Origin of mass defect
First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for mass defect
physics the amount by which the mass of a particular nucleus is less than the total mass of its constituent particlesSee also binding energy
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