Noun: "a discussion or meeting for the purpose of assigning blame"
This word was added to Webster's around 2009, and I don't think I have ever heard anybody use it. Apparently blamestorming happens enough across corporate America that this weird word needed to be officially added to the English language. Maybe if we just stopped passing the buck and accepted actions as our own fault this entry wouldn't exist today. Accept responsibility; stop the blamestorming!