The most common symbol of the disc is the pentagram inscribed in a circle, commonly called a pentacle, although some other symbols may be used such as the triquetra.
Like the triskelion, the triquetra, and their antecedents (e.g., the triple spiral), the symbol of the three hares has a threefold rotational symmetry.
The symbol appears in unicursal form, topologically a trefoil knot also seen in the triquetra.
The triquetra symbol has been known to change, usually according to some change in the sisters' powers or emotional state.
It was written in a different font and is still underlined and sometimes featured a triquetra above the name.