DEFINITION of 'Eurozone'. A geographic and economic region that consists of all the European Union countries that have fully incorporated the euro as their national currency. Also referred to as euroland.
variation. n. 1. the act, process, condition, or result of changing or varying; diversity. 2. an instance of varying or the amount, rate, or degree of such change. 3. something that differs from a standard or convention.arâ¢iâ¢aâ¢tion. 1. the act or process of varying: prices subject to variation. 2. an instance of this: a variation in quality. 3. amount of change: a temperature variation of 20Â°. 4. a different form of something.
Antigenic variation refers to the mechanism by which an infectious agent such as a protozoan, bacterium or virus alters its surface proteins in order to evade a host immune response. It is related to phase variation.ntigenic variation is the expression of various alternative forms of antigen on the cell surface. Whereas phase variation is the phenotypic switch that is usually reversible and is referred to as an ON-OFF switch.