sērĭō: adv., v. serius.
sērĭō,¹¹ sérieusement : Pl. Amph. 906 ; Ter. Haut. 541 ; Liv. 7, 41, 3 ; Plin. Min. Ep. 2, 20, 10.
sēriō, Adv., s. 1. sērius, a, um.
αὐθάδης, βαρύς, ἐμβριθής, ἀγέλαστος, ἀδιάχυτος, ἄμωκος
serio ADV :: seriously, in earnest