Strong G7752καθαρεύω

to be clean or pure , (Plato Philosophus): —;with genitive to be clean or free from guilt, (Plutarch); also, κ. ἀπ᾽ αὐτοῦ (i.e. τοῦ σώματος); (Plato Philosophus); also, καθ. γνώμῃ to be pure or clear in mind, (Aristophanes Comicus) (ML)