διεῖδον · dieidon — LSJ
see thoroughly, discern (on the Homeric usage v. δια-είδω), τι Ar. Nu. 168, Pl. Phdr. 264c; λόγος οὐ ῥᾴδιος διϊδεῖν Id. Phd. 62b.
see through:—Pass., διειδομένη ἐν ὕδατι νῆσος Call. Del. 191; ἀτραπὸς . . διειδομένη πεδίοιο seen through or across the plain, A.R. 1.546.