Definitions for "Variable star"
Any star that exhibits intrinsic changes in light.
star whose brightness changes periodically. There are many types of variable stars and their brightnesses vary for many different reasons. For example, the brightness of a Cepheid variable star changes because its luminosity changes; the luminosity change is related to the internal structure of the star and the processes that occur there. Variable stars can also be caused by eclipsing dark or bright companions
A star whose brightness changes over time. A to F | G to L | M to R | S to Z