>>11321610All the wrestling jargon came from the carnivals, so you'd have circus guys and a shitload of acts all speak the same insider words that the crowd wouldn't know like ballyhoo and mark, and then suddenly the vaudeville talent shows up for television in the late 1940s and throughout the 1950s talking carny with the TV producers, and meanwhile the theatre guys and stagehands are all working the carnivals here and there.
A pop is just a word for a crowd reaction. They don't have marks in typical TV show audiences, but sometimes they do have a plant who's kayfabing ignorance but is in on the work.
In on what work? Working the crowd.