I. | ̷ ̷| ̷ ̷ verb
Etymology: Middle English upbreken, from up + breken to break — more at break
transitive verb
: to break up or open
intransitive verb
: to force a way up (as through the surface)
II. ˈ ̷ ̷ˌ ̷ ̷ noun
: an act or instance of breaking up ; especially : eruption , outburst