Seasonal affective disorder (SAD), also known as winter depression, is a mood disorder whose sufferers experience normal mental health throughout most of the year, but experience ...
http://en.wikipedia.org/wiki/Seasonal_affective_disorder

Sadness is an emotion characterized by feelings of disadvantage, loss, and helplessness. When sad, people often become quiet, less energetic, and withdrawn.
http://en.wikipedia.org/wiki/Sad

Photobucket - Upload, view and share sad pictures, sad images and sad photos online. ... Official Britney Spears Group Album Britney Spears Official Group Album! Comments are here ...
http://photobucket.com/images/sad/

Information about seasonal affective disorder from the American Academy of Family Physicians. ... Seasonal affective disorder (also called SAD) is a type of depression that is ...
http://familydoctor.org/online/famdocen/home/common/mentalhe ...

Symptoms. The symptoms of SAD usually recur regularly each Winter, starting between September and November and continuing until March or April.
http://www.sada.org.uk/symptoms.htm