Circular Logic

AITOOW realizes that "circus" comes from "circle"? I never understood the Picadilly Circus. More questionable English english. As a kid, I thought there once must have been a circus there in olden days. Same with the Circus Maximus. I thought it had been a big circus pavilion. And I'm guessing a circus is a circus because of the shape of the performing areas. Odd. There are so many other things they could have named it after (place where dozens of  ghost faced demons exit an automobile) that they chose the "stage" as the most evocative. Love those etymologies. Just realized "diocese" must have something to do with "dio" (ie God) as well.