Main Entry: erup·tion

Pronunciation: \i-ˈrəp-shən\

Function: noun

1 : an act, process, or instance of erupting <the eruption of the tooth from the gum> ; specifically : the breaking out of an exanthem or enanthem on the skin or mucous membrane (as in measles)
2 : something produced by an act or process of erupting: as a : the condition of the skin or mucous membrane caused by erupting b : one of the lesions (as a pustule) constituting this condition