ἀπαρεγχειρήτως

From LSJ

γελᾷ δ' ὁ μωρός, κἄν τι μὴ γέλοιον ᾖ → the fool laughs even when there's nothing to laugh at

Source

Russian (Dvoretsky)

ἀπαρεγχειρήτως: безукоризненно, совершенно (ὡμοιωμένος τινί Diod.).

Spanish

insuperablemente, perfectamente