This fabulous slogan, usually written in two lines of block capitals on a T-shirt or bumper sticker, illustrates the attitude of the University of Michigan toward one of their biggest football (American football, that is) rivals, Ohio State University. In fact, it illustrates their attitude toward most of their fellow Big Ten competitors.
Ohio State, though, has a history of making Michigan look bad right at the end of the season. (Michigan often makes Ohio State look bad right at the end of the season as well -- they have been pitted against each other for each of their last Big Ten conference games for years. So it's not as if Ohio State likes Michigan, either.) Last year, for instance, their season-closing match ended in a loss of 20 to 26, before the second largest crowd ever to grace the incredibly ugly Michigan Stadium. Yay, humiliation at home!
Rabid Michigan fans (of which there are LOTS) do not take too kindly to such losses, somehow. So! Much jeering and catcalling tends to ensue.
This particular slogan is interesting because it is designed to fool the viewer for a moment. The entire first line is run together as one word, while the second is clearly "OHIO STATE". The slogan itself is often printed in white on a red shirt: Ohio State's school colors. On first glance, a casual observer might take this T-shirt as a show of support for Ohio State. A closer look, however, reveals the actual slight. So it's not just an insult, it's a clever, underhanded insult.
By reverse, this slogan is also a dramatic (yet nasty) show of support for Michigan. "We love you so much that we spit on your enemies!" -- that sort of thing.
Disclaimer: I hate football, and have no interest in either team. I just happen to live in Ann Arbor.