Here's a breakdown:

* Active volcano: A volcano that is currently erupting or has erupted recently, showing signs of activity like steam vents, gas emissions, or seismic activity.

* Dormant volcano: A volcano that is not currently erupting but has the potential to erupt in the future. It shows signs of past activity and may have the potential to become active again.

* Extinct volcano: A volcano that is considered unlikely to erupt again. It has no signs of recent activity and its internal plumbing system is likely cooled and solidified.

So, while "inactive" might be used casually, "dormant" or "extinct" are more precise terms to describe the opposite of an active volcano.