What is "pentagrams"

Usage examples of "pentagrams".

The pale silver dome covered fully an acre, and it was marked at the four cardinal points and the zenith by flaming pentagrams traced in different colors and set round with the sigils of the elements.

Then they threw some pentagrams around and copied runes out of a book.

It is a complicated matter of runes and pentagrams, fragrant herbs and words of power, which I will not describe to you because it would permanently unhinge your already weak mind, old fellow.