[Coolhwip]

http://www.playdota.com/learn/commonterms Although "ss" isn't in there..

"ss" is the same as "miss" and "mia".

During the Battle.net days no one said "ss", everybody started with typing "missing" then it became "miss" or "mia" and later on "ss".
"ss" kind of became a shorter term of a shorter term.

I guess frog hasnt updated that index in a while.