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It means they have a Masters of Science.
Masters of Science Degree
That person has a Masters Degree.
It might mean a Masters in Health Science
Masters of Arts
Educational Specialist. It is a degree between a Masters and an Doctorate.
The thing you stand behind when giving a speech is called a podium or a lectern.
MSN = Masters in the Science of Nursing. It means they are a nurse, not a doctor.
Master of Science
groomsmen
a podium.
DO stands for Doctor of Osteopathic Medicine.