Winter Solstice
The winter solstice is the moment when the earth is at a point in its orbit where one hemisphere is most inclined away from the Sun. The word solstice is from Latin solstitium, from sol ‘sun’ and sistere ‘to stand still,’ as it is regarded as a point at which the Sun seems to stand still. The day of the winter solstice is the shortest day and the longest night of the year.
SOURCES & MORE INFORMATION:
http://www-spof.gsfc.nasa.gov/stargaze/Sseason.htm
http://dictionary.reference.com/features/winter.html