ἐν πέτροισι πέτρον ἐκτρίβων → by grinding stone against stones
precarious: P. ἐπικίνδυνος, ἐπισφαλής.
critical point: P. and V. ἀκμή, ἡ; see crisis.
censorious: P. and V. φιλαίτιος, φιλόψογος.
exact: P. and V. ἀκριβής.
