Fan emerged from American sports slang in the 1880s and quickly became a useful umbrella term to describe similar enthusiasts in other realms, such as theater, cinema, jazz, and science fiction. However, fan was not the first instance of English-language slang to describe sustained and passionate engagement with a cultural object or pursuit. The mid-nineteenth century was obsessed with monomania and connoisseurship; before that, enthusiasm and the passions were a hot topic of Enlightenment debate. And specific instances of fan-like groups were noted by a range of colorful terms, from bug to matinée girl. For those researching historical fandom, the various meanings and uses of various names, appellatives, and labels can reveal changing ideas about avid people and behaviors, across social contexts and time periods. Overall, the rich vocabulary of pre-fan terms can help build a wider history of fandom.