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Noun: mass number
  1. The sum of the number of neutrons and protons in an atomic nucleus
    - nucleon number

Derived forms: mass numbers

Type of: mass unit

Encyclopedia: Mass number

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mass defect
mass deficiency
mass energy
mass extinction
mass hysteria
mass medium
mass meeting
mass murder
mass murderer
mass noun
mass number
mass production
mass rapid transit
mass spectrograph
mass spectrometer
mass spectroscopic
mass spectroscopy
mass spectrum
mass unit
Massachuset
Massachusetts