A circus that displays people with abnormal or unusual oddities. Examples of such people include
bearded women, Siamese twins, or in the case of The Saga of
Darren Shan, a woman who can bite through steel, a man with two bellies, a vampire and his spider, a snake boy, a man who is afraid of the ground, a
monkey girl, et al. Legal back before television was invented.
A
freak show back in those times had evil con men
rounding up people who had physical deformities, putting them in cages, paying the public to stare at them and forcing them to perform insane tricks that could hurt or kill normal people who imitated them. The people who saw these freak shows were just as disturbed as the people who ran them. These shows are now illegal because of the abusive nature, and the discrimination these performers faced because the public were conned into thinking that they were freaks, which meant that they were misunderstood by those who realized that they were entirely normal and that the real freaks were the people who ran these human circuses. Although there are exceptions like American Horror Story:
Freak Show, and
Cirque du Freak where there would be actual freaks running the shows, these were in the minority. Today, there might be shows like this which we call
reality television, which displays people like Abby and Brittany, who would have qualified to be in a freak show if they were around when those things were legal. They are scary depending on the acts that are performing.