ἀρριγής
From LSJ
ἐν ταῖς ἀνάγκαις χρημάτων κρείττων φίλος → it is better in times of need to have friends rather than money, a friend in need is a friend indeed (Menander, Sententiae monostichoi 143)
English (LSJ)
ές, = sq. Adv.
A -γέως Hp.Acut.29.
Greek (Liddell-Scott)
ἀρρῑγής: -ές, = τῷ ἐπ.· ἐπίρρ. -γέως, Ἱππ. Διαίτ. Ὀξ. 388.