Freak in the context of "Freak show"

A freak show is an exhibition of biological rarities, referred to in popular culture as "freaks of nature". Typical features would be physically unusual humans, such as those uncommonly large or small, those with extraordinary diseases and conditions, and others with performances expected to be shocking to viewers. Heavily tattooed or pierced people have sometimes been seen in freak shows (more common in modern times as a sideshow act), as have attention-getting physical performers such as fire-eating and sword-swallowing acts.