atrial fibrillation. n. Abbr. AF. Fibrillation in which the normal rhythmical contractions of the cardiac atria are replaced by rapid irregular twitchings of the muscular wall that cause the ventricles to respond irregularly. Also called a-fib, auricular fibrillation.
continental=on land. here is a good example of plate tectonics, i just had to explain all that stuff. Subduction is when converging plates come together. they make a trench by one plate sliding under the other and into the mantle.
Tectonic plates move around and can cause earthquakes and volcanic eruptions. First of all, it is important to know that the Earth's crust is broken up into large pieces called tectonic plates. Remember, tectonic plates are giant pieces of the Earth's crust that fit together and move around on the Earth's surface. This movement can be observed and measured using GPS systems, and the edges of the plates can be detected, as their edges can be seen. We also know that these plates move around with respect to one another.