Oh, how I chortled when I read this submission to our Reduce Idiocy campaign! And then I went back to drinking my tea with my pinky finger in the air:

Once, when I was in medical school, we were discussing the muscles of the face and, in reference to the eye, someone referred to the orbicularis oris. How we laughed because, of course, she meant orbicularis oculi!

I'm sure this submission from a "doctor in training" is a pompous-on-purpose joke, mostly because I am married to said doctor in training. Still, not wanting to embarrass myself at any future medical-community tea parties, I looked up the difference between the orbicularis oris and the orbicularis oculi, and it did turn out to be rather substantial: The orbicularis oris (below left, from Gray's Anatomy) is the muscle around the mouth that allows you to make funny faces, while the orbicularis oculi (below right in dark pink, ditto) is the muscle that lets you close your eyes.