This is what stupid people say when they, in fact, mean, "I couldn't care less." The intent of the phrase is to express the fact that the level of caring the user has is nil. However when taken literally, the phrase dictates that there is at least some level of caring and it is possible to care less. Some people have said that the phrase is used sarcastically and that people who use it know that the meaning is opposite to the literal interpretation. However it is far more likely that people who say, "I could care less," and mean the opposite are just stupid.
n. Someone who deliberately attempts to prevent a guy from seducing a girl. The opposite of a wingman. Similar to a cockblocker, but while a cockblocker may not necessarily be acting deliberately, a MiG always is. The MiG does not necessarily have to be trying to seduce the girl him/herself, but that is possible. Often the MiG is a friend or acquaintance of the guy who is attempting to seduce the girl. The term is derived from the film 'Top Gun', where the enemy planes were MiGs that were attempting to shoot down the protagonists.
v. The act of deliberately attempting to prevent a guy from seducung a girl.
That douche really pissed me off today, so I'm going to MiG him tonight at the bar.
Person 1: Hey, what happened to that hot chick you were talking to?
Person 2: My mate thought it would be funny to tell her I was convicted of domestic violence, so she fucked off.
Person 1: Man, you were totally MiGged!
Person 1: If you're going to try it on with that chick, you'd better be careful - there are enemy MiGs circling!
Person 2: Who?
Person 1: Me! Haha!
Person 2: You're such a dick, you're supposed to be my wingman!