The term epicenter is a term that is used in the area of geology, also in that of geography, to designate that place located on the surface of the Earth from which a phenomenon such as an earthquake or tsunami arises, or any other seismic movement. The term epicenter comes from the Greek, a language in which the prefix epi means over or over. Thus, the idea of the epicenter refers us to the fact that the place marked as such is the place from which the seismic movement becomes visible on the surface, the center from where it starts off to its surroundings.
When we speak of the epicenter in the aforementioned areas, we are always referring to those seismic movements that occur from the movement of the tectonic plates and that cause terrestrial or aquatic displacements, slightly or severely altering the life of the human being and also of the rest of the living beings. This is so because seismic movement always involves vibrations, ground breaking, displacements, etc. that change the landscape of a region geographically and spatially.
The epicenter of these seismic movements is the place from which the earthquake or vibrations started. The epicenter is the place where the tectonic plates moved and, once that movement reached the surface, it began to move by the very force of the movement in the form of circles or waves (which become more and more expansive but with less force at as they move away from the epicenter) towards the surroundings.
When speaking of an epicenter, the place from where the earthquake or tsunami starts is then pointed out in order to determine which places on planet Earth are more prone to these phenomena, as well as being able to determine which are the areas most severely affected and paralyzed by the phenomenon itself.