Which of the following best defines the term 'dormant volcano'?

The term 'dormant volcano' is best defined as a volcano that has not erupted in a long time but has the potential to erupt again in the future. This classification acknowledges that while the volcano is currently inactive, it is not considered extinct. Dormant volcanoes are often monitored by volcanologists for signs of potential activity, as their eruptions can be unpredictable and can occur after long periods of dormancy.

In contrast, a volcano that is currently erupting is actively active and doesn't fall into the dormant category. An extinct volcano, on the other hand, is one that has shown no signs of erupting for a significant amount of time and is believed to be unlikely to erupt again. A volcano that is underwater may have certain characteristics but does not directly define its activity status; thus, it doesn't specifically relate to the concept of dormancy.