[1] Nominative plural of this noun, evidently quoted from somewhere. Same definition given in Hesychius, Photius, the Lexica Segueriana. Also in severl scholia: to Nicander, Alexipharmaca 548; Clement of Alexandria, Protrepticon & Paedagogus p. 302 Stählin & Treu; and Theocritus, Idylls 5.48.
[2] Definition given in Theognostus, Canons p. 356 Cramer. The allusion appears to be to the shadows cast by the earth as a planet (i.e. night or an eclipse), although the precise wording is late in coming: Sophonias (13-14 c. CE) Paraphrase on Aristotle, De Anima p. 79 Hayduck "for the conical shadow (ἀποσκίασμα ) of the earth, which is night, does not overtake the sphere of the moon"; Alchemical Fragments, eds. Berthelot and C.É. Ruelle, Collection des anciens alchimistes grecs, vol. 2. Paris, Steinheil, 1888 p. 274: "when the shadow of the cone of the earth reaches the sphere of Hermes."