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.
The theory of plate tectonics states that the plates of the earth move due to convection in the mantle. This is what brings continents together and apart. Plate Tectonics statâ¦es that Earth's crust and the outermost part of the mantle are mechanically connected to each other. This layer is broken into several plates that move about Earth's surface.