Pentagram

A pentagram was an ancient symbol of the occult. It was usually represented by a five-pointed star encircled by a continuous ring. This could be displayed one point upwards, or two points upwards, depending on its use.

In 2269, the crew of the USS Enterprise (NCC-1701) encountered the Megans, who were a race of magical, timeless creatures.

Spock drew a pentagram, which he referred to a "mystic symbol", as he attempted to toy with the art of magic. While standing inside the pentagram, he successfully moved a Vulcan chess piece with his newfound "powers."

A pentagram later appeared on the ground during the trial over the crimes of Humanity against the Megans.