What is the abbreviation for office manager?

I would like to mention here that Office Manager has no known abbreviation in the English language. Words like Dep't, sos, ltd, have always been known. However, Office Manager loses its meaning and taste if abbreviated and to me would be a new phenomenon. Just write O/M OR OM on a sheet of paper and ask your friend what it means. He can make neither tail nor head for it. Believe me.Thus, its usage should be abhorred by all means. Jabhad.jabhad@Yahoo.com