ἀκρόκνεφα

ον, ές
A. at beginning of night, in twilight, Hes. Op. 567:—also ἀκρο‐κνεφής, ές, of morning twilight, Luc. Lex. 11, Id. Rh.Pr. 17; cf. ἀκρόκνεφα· πρὸς ὄρθρον, Hsch.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
An open-access project