Grand Poobah explained

I was jokingly referring to a colleague as Grand Poobah the other day and wondered, where did that come from?

Grand Poobah is a term that originates from Gilbert and Sullivan's The Mikado. In this operetta, the haughty character Pooh-Bah holds numerous exalted offices, including Lord Chief Justice, Master of the Buckhounds, Lord High Auditor, Groom of the Back Stairs, and Lord High Everything Else. The name has come to be used as a mocking title for someone self-important or high-ranking and who exhibits an inflated self-regard.

I used to work in a consulting firm. This word, in its mocking form, would fit many of the partners there. Some were a particularly weird combo -- inflated self-regard with an insatiable need for attention and acceptance. It could be tiring.