What are three other arachnids besides spiders?

Spiders have all kinds of names. Sometimes people call two or more entirely different kinds of spiders by the same name. That is why scientists prefer to use their own terms, names in Latin that give both a genus and a species.

One example of confusing naming is "banana spider." Sometimes people used that name to apply to a very large spider from the Amazon River region that has enough venom to kill five people. That kind of spider often hides out in clusters of bananas and when the cluster gets harvested the spider may go along for the ride. (Not too long ago one of them showed up in a restaurant kitchen in London.) But people also use the name to apply to a whole genus of spiders that make very large webs using a kind of gold-colored silk. These spiders are also very large, and some of them are mostly yellow. But other than the color they have nothing to do with bananas. They are also harmless. There may be other spiders that get called banana spiders because they are large and mostly yellow. The problem is when somebody says something like, "Banana spiders can't hurt you," and the other person then tries to get friendly with the Brazilian Wandering Spider. Or somebody may claim, "Banana spiders are the deadliest thing on eight legs," and somebody in Florida may totally freak out because their home has the webs of some of the big spiders that would only bite you if you grabbed one and put it in fear for its own life, and that would not do any great damage even if they did give you a defensive bite.

People give their pet spiders all kinds of names. Who knows why?