erupt, break out: start abruptly "After 1989, peace broke out in the former East Bloc"
erupt, irrupt, flare up, flare, break open, burst out: erupt or intensify suddenly "Unrest erupted in the country", "Tempers flared at the meeting", "The crowd irrupted into a burst of patriotism"
erupt, belch, extravasate: become active and spew forth lava and rocks "Vesuvius erupts once in a while"
break, burst, erupt: force out or release suddenly and often violently something pent up "break into tears", "erupt in anger"
erupt: appear on the skin "A rash erupted on her arms after she had touched the exotic plant"
erupt, recrudesce, break out: become raw or open "He broke out in hives", "My skin breaks out when I eat strawberries", "Such boils tend to recrudesce"
