FB:OD simply stands for facebook overdose. The colon is there for like no reason, but FB:OD occurs when someone gets on facebook without expecting much, and has an excessive amount of notifications, causing them to be overwhelmed, and leave without reading them all.

v. collectively or individually finding someone/something to blame for a problem, as opposed to brainstorming which connotes finding solutions to a problem

n. the act of finding someone/something to blame for a problem

(from a TV ad for HD television)