poobah
A person who holds multiple offices or positions of power at the same time.
A leader or other important person.
‘I said pooh-pooh,’ Duxmann Pooh Bah said.
A pompous, self-important person.
Where it comes from
From Pooh-Bah, a comic character in the Gilbert & Sullivan operetta The Mikado (1885), formed as pooh + bah, both expressing contempt. The character of W. S. Gilbert's libretto is preceded by the character Pish-Tush-Pooh-Bah (described as “haughty”) in “King Borriah Bungalee Boo” (1866), one of the Bab Ballads, with pish and tush being two other terms of contempt.
Adapted from the Wiktionary entry poobah (CC BY-SA 4.0).