I don’t know if this is new, or interesting to anyone other than me, but I came across a definition of a “star” in the entertainment context:
[an answer to a correspondent in Philadelphia:] A “star” is an actor or actress who plays brief engagements at theatres throughout the country, receiving a certain share of the gross receipts of each night’s performance. New York Clipper September 7, 1867
I don’t know how seriously to take this claim, but it does make a certain sense. The Clipper was a major entertainment newspaper, though I am reading it for its early baseball coverage.