A pooh-bah is a person who has a lot of power in government, usually by holding several positions or offices at the same time. Sometimes the pooh-bah knows that he or she has this power and is pompous or overemphasizes his or her worth.
The plural is pooh-bahs.
The term is sometimes capitalized because it started out as a proper noun. Pooh-Bah comes from a fictional work written in 1885, where the Grand Pooh-Bah acts much like the definition listed above. In our research, we found that it is mostly capitalized when someone is referring to the actual character from the play. Most other usage does not retain the capitals, perhaps for lack of knowledge of the origin of the term.
The hyphenated spelling is the official listing in most dictionaries. However, as almost all hyphens seems to get transitioned out eventually, the more commonly found spelling is poobah. If we were to guess, this is similar to the loss of capitalization and comes from people learning the term without knowing the historical context.
In usage, the non-hyphenated version is more common, though not by much. Sometimes it is used in the phrase grand poobah. Now, sometimes people capitalize Grand Poobah. We are hesitant to call this an error, simply because the term is in flux and if the word grand makes the term a title, no matter the spelling, then capitalization would be required, even if the term has lost all reference to the original name.
To reiterate, the dictionary-preferred spelling is pooh-bah, no capitals. It should also be noted that the phrase grand poobah, in any form, is not listed in the dictionary.
Nervously, the 6-foot-6 player for the Seattle SuperSonics headed into the pooh-bah’s office. [New York Post]
He’s acknowledged to be the grand pooh-bah of poinsettia-growing in Canada. [Toronto Star]
The video screens relay images related to the narrative: at one point, a mob of hip-hop fans; at another, the goofily sinister visage of Mo’ Money (a very funny Jacob Yeh), a record label poobah. [Washington Post]
Yesterday, Bruins grand poobah Cam Neely told the “Felger and Mazz Show” that management certainly has looked back on the entire matter of Tyler Seguin and suggested he might have needed a bit more support and monitoring when he first arrived as an 18-year-old Canadian kid alone in the big city. [Boston Herald]