make a thing sure: P. βεβαιοῦν.
verify: P. ἐπαληθεύειν.
ratify: P. and V. κυροῦν, ἐπικυροῦν, ἐμπεδοῦν (Plato, also Ar.).
encourage: P. and V. θρασύνειν, θαρσύνειν, P. ἐπιρρωννύναι; see encourage.