ˈ ̷ ̷| ̷ ̷ ̷ ̷ ̷ ̷- noun
: an equation for the interconversion of mass and energy: E = mc 2 where E is energy in ergs, m is mass in grams, and c is the velocity of light in centimeters per second — called also Einstein equation ; compare conservation of energy , conservation of mass