What does it mean when planets are in retrograde?

Retrograde-   /ˈretrəʊˌɡreɪd/ “Directed or moving backwards” What is retrograde? There are certain periods throughout every year when the planets move in the opposite direction than they normally do. This is when the planets move in retrograde. How long are planets in retrograde? The time period each planet is in retrograde varies. The outer planets of …