Funny you should ask. We just completed a 6-patient simulated OSCE today. OSCE stands for Osteopathic Structured Clinical Exam. 6 patients, each with a different chief complaint. You have 10 minutes to go in, interview and do any physical exam you might need, then you have 5 minutes to write your soap note. No talking to anyone outside the room. You are videotaped and given the tapes to go home and do a self-evaluation. Of course, there is another tape for those giving the exam to evaluate. So what kind of cases?
My first case was a lady with left lower quadrant pain, diarrhea, etc. Second patient, sprained ankle. Third patient, given wrong medication following surgery and was suffering from dizziness. Fourth patient, breast lump. Fifth patient, extreme hyperactivitiy (maybe thyroid related?) with palpitations. Last patient, tightness of chest with shortness of breath. Sent her to the hospital.
It was fun. But it was quite eye-opening to see just how hurried it all can be. Now I have the weekend to view the videotape and turn my self assessment in next week. I have a feeling I may be horrified when I watch my tape.
Wow! Is second year ever fun! 
Or it could mean Objective Structured Clinical Exam/Encounter. As above but also in allopathic schools. It is one way to help evaluate your clinical skills. Sometimes they might have self-evaluation. Othertimes it is evaluated and graded.
I was just about to reply with the same answer. Many of my MD colleagues also took OSCE exams except that in lieu of O = Osteopathic it stood for O = Objective…which, in my humble opinion, is much more accurate & conveys the import of the exam.
All right. So I screwed up the name. 
The experience was the same! 
Actually, I think at KCOM the O did = osteopathic; so you may not be mistaken.
Anytime you see an “O” in an acronym in DO school, it’s a safe bet it means ‘osteopathic’.
OSCE, OPTI, OMM, OMT, OMS … The list goes on.