A person who is anti social or generally lame and sad. They may sit at home on New Year's and mope in their own sadness even if they have been invited out
"Merwyn is such a sadpuss sitting at home on New Year's"
"FINE then be a New Year's sadpuss like Merwyn"
"FINE then be a New Year's sadpuss like Merwyn"
by Savannah Fernandes September 26, 2008