Astronomically dwarf planet 2003 UB313 / 136199 "Eris", astrologically planet Persephone/Proserpina/Kora.
Symbol: cross over circle (matter over spirit), cross decorated with additional smaller perpendicular lines.
"Astrological meanings" proposed from the name "Eris" in the USA do no fit to the nature of this new planet. Observed in charts, it's most similar to sign of Taurus. Few Polish astrologers, among them Jarosław Gronert and me, made research on this*, and most of us researching it in Poland settle on the names Persephone/Proserpina/Kora.
The more deep reason for haste with it's announcing in 2005 in restropection now three years later is better understood. The summer of 2005 was the first summer where 1/8 of the arctic (north) polar cap melted, this meltdown reaching as much as 25% in the summer of 2007. Climate change is now confirmed as one of the most profound keywords for this new planet, and in common words "The Spring" is one of her basic meanings.
Btw the season before spring in Taurus - times in Pisces/Aries are quite violent season of the year (especially in countries where rivers flow from south to north like Poland); and she is now still in Aries...
* Jarosław Gronert "Astrologia od początku" 2007 Pabianice, Poland, see more at: www.jarekgronert.pl