noun 2. a throwing forth of lava, water, steam, etc. 4. Medicine a. a breaking out in a rash
b. a rash
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
Mifflin Harcourt. Published by Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'eruption'ME erupcioun < L eruptio: see erupt