A volcano which has not erupted for many years can be described as dormant. The word dormant is derived from the French, dormire, meaning to sleep.
Such a volcano is dormant.
You would call this volcano dormant. Dormant means that the volcano could erupt but right now the volcano is inactive/dormant.
Simply an "active" Volcano. If it has NOT erupted for a long time it can be a "dormant" or "extinct" Volcano.
A volcano that has erupted recently is considered active. In the time before it erupted, if it had not previously erupted in historic times, it is considered dormant.
Dormant
A "Dormant Volcano"
dormant
You call a volcano that is no longer active (erupting, or any other seismic activity) dormant.
This is described as a dormant volcano (neither active nor extinct).
Molten rock below the surface of the Earth is known as magma. After it erupts from a volcano it is called lava.
Molten rock below the surface of the Earth is known as magma. After it erupts from a volcano it is called lava.
What you call molten rock after it has erupted is lava.