An active volcano is a volcano that has had at least one eruption during the past 10,000 years. ... A dormant volcano is an active volcano that is not erupting, but supposed to erupt again.
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Volcanoes are classified as active, dormant, or extinct. Active volcanoes have a recent history of eruptions; they are likely to erupt again. Dormant volcanoes have not erupted for a very long time but may erupt at a future time. Extinct volcanoes are not expected to erupt in the future.
