Why are movie previews called trailers? It would only make sense if they came after the movie, or trailed them. Well, that's the thing: they actually used to for several decades. There would be a quick teaser after the feature, to build anticipation for its sequel. This was soon extended to any other upcoming films in general, and then marketing executives had an epiphany. What if they put trailers at the beginning of films? Then people would be forced to see them and not duck out during the credits. Thus, something supposed to trail a movie ended up preceding it. Anyway, the noun trail comes from the verb trail, which was borrowed in the 1300s from the Old French word trailler, which meant something like "drag". Trailler hails from Latin tragula, meaning "dragnet", which either comes from or is related to trahere, "to pull". This would come from the Proto-Indo-European reconstruction tragh, with a similar definition.
Adam Aleksic, a freshman studying linguistics at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in words, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd