noun that which bursts forth.
2. eruption ·noun a violent exclamation; ejaculation.
3. eruption ·noun the breaking out of pimples, or an efflorescence, as in measles, scarlatina, ·etc.
4. eruption ·noun the act of breaking out or bursting forth; as: (a) a violent throwing out of flames, lava, ·etc., as from a volcano of a fissure in the earth's crust. (b) a sudden and overwhelming hostile movement of armed men from one country to another. milton. (c) a violent commotion.