ἐθελουσίως
From LSJ
τὸ κοῖλον τοῦ ποδὸς δεῖξαι → show the heels, show a clean pair of heels, show the hollow of the foot, run away
French (Bailly abrégé)
adv.
volontairement.
Étymologie: ἐθελούσιος.
Spanish
por propia voluntad, espontáneamente
Russian (Dvoretsky)
ἐθελουσίως: Xen. = ἐθελοντηδόν.