When lava begins to pour from a volcano, this is an example of erupt.
When you hold anger inside often but you suddenly get fed up and lash out yelling, this is an example of a time when you erupt in anger.
When you suddenly break out in hives, this is an example of a time when hives erupt.
Erupting lava; a riot erupted.
Violence erupted during the protests.
He erupted in anger.