(physics) Mass and energy as a unified concept. / (also spelled mass energy) The energy associated with any given mass according to special relativity, E = mc².

mass-to-energy

(physics) A mass of fissile material that is more than sufficient to sustain a nuclear chain reaction

(physics) A mass of fissile material that is insufficient to sustain a nuclear chain reaction.

Third-person singular simple present indicative form of mass-produce

present participle of mass-produce

(physics) Half of the harmonic mean of two given masses.

plural of mass flow

(physics) mass defect

(chemistry) The fractional proportion of a substance in a mixture, by weight/mass.