キラル

Chirality /kaɪˈrælɪtiː/
Derived from the Greek χειρ (kheir), "hand," a familiar chiral object.

To have chirality is to possess optical isomerism; for instance, a left hand and a right hand.
In chirality, an object’s image and its mirror image cannot be superimposed. That is, when one is placed over the other, the image is distinguishable.

From “Daijirin Third Edition”