δυσέφικτος
From LSJ
οἱ βάρβαροι τῇ ἀλήκτῳ συνουσίᾳ ὑπνώθησαν → the barbarians, exhausted by unremitting intercourse, fell asleep
English (LSJ)
ον,
A hard to come at, Plb.31.25.3, Plu.2.65e, Phld.Rh.2.119 S.; ἀνθρώπῳ Ecphant. ap. Stob.4.7.64; hard to understand, Vett.Val.272.8, al.