intentionally
From LSJ
κράτιστοι δ᾽ ἂν τὴν ψυχὴν δικαίως κριθεῖεν οἱ τά τε δεινὰ καὶ ἡδέα σαφέστατα γιγνώσκοντες καὶ διὰ ταῦτα μὴ ἀποτρεπόμενοι ἐκ τῶν κινδύνων → the bravest are surely those who have the clearest vision of what is before them, glory and danger alike, and yet notwithstanding, go out to meet it | and they are most rightly reputed valiant who, though they perfectly apprehend both what is dangerous and what is easy, are never the more thereby diverted from adventuring
English > Greek (Woodhouse)
adverb
P. and V. ἑκουσίως, ἐκ προνοίας (Euripides, Hercules Furens 598), P. ἐκ παρασκευῆς, V. ἐξ ἑκουσίας; see deliberately.
Or use adj., P. and V. ἑκών; e. g., kill a person intentionally: P. and V. ἑκὼν ἀποκτείνειν (τινά).