A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # Select the first letter of the word from the list above to jump to appropriate section of the glossary. If the term you are looking for starts with a digit or symbol, choose the '#' link. - R - Ra Egyptian Sun god during a brief monotheistic fling during the days of the Pharoahs. retrograde Apparent backwards (ie, from the west to the east) movement of a planet, an artifact of orbital perspective. Back to Top