CHARLOTTE, N.C.—The under-40 set took majority control of the city council last fall with new priorities for one of America’s fastest-growing cities. One was to live-stream meetings. Another was banishing the term millennial.

“We made a conscious effort to abandon the word,” said City Councilman Larken Egleston, a 35-year-old liquor salesman and Democrat. “It was often used to describe us as a group as not ready or whatever it’s code for.”

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