E*rup"tion (?), n. [L. eruptio, fr. erumpere, eruptum, to break out; e out + rumpere, to break: cf. F. 'eruption. See Rupture.]
1.
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.
All Paris was quiet . . . to gather fresh strength for the next day's eruption.
W. Irving.
2.
That which bursts forth.
3.
A violent exclamation; ejaculation.
He would . . . break out into bitter and passionate eruditions.
Sir H. Wotton.
4. Med.
The breaking out of pimples, or an efflorescence, as in measles, scarlatina, etc.
© Webster 1913.