Fig. 1: Single-tetrahedron chirality.
From: A classical chiral spin liquid from chiral interactions on the pyrochlore lattice

Illustration of an up-tetrahedron with the direction of the chiral term specified for two of its faces, S0 ⋅ (S1 × S2) and S0 ⋅ (S2 × S3). Here, the black arrow denotes the high-symmetry [001] and [110] directions.