ἐν πέτροισι πέτρον ἐκτρίβων → by grinding stone against stones
ἐκβολή, ἐκπέτασις, ἀνάλημμα, ἔκπτωσις, ἐξάπλωσις, ἀποσκιασμός, ἔκχυσις
