Thayer's
STRONGS NT 2576: καμμύωκαμμύω, a form which passed over from the epic (cf. 
Homer batrach. 191) and common language (
Apoll. Dysc. synt. 323, 22; 326, 9) into the Alexandrian and decaying Greek; condemned by Phryn. (as below); derived by syncope and assimilation from 
καταμύω (which the earlier and more elegant Greeks use) (cf. 
καμμέν, 
καμμονη, 
κάμμορος, from 
κατά μέν, 
καταμονη, 
καταμορος, cf. Alexander 
Buttmann (1873) Gram. § 117, 2 Anm. 2; Ausf. Gram. ii., p. 373; Fischer, De vitiis lexamples N. T., p. 678f; Sturz, De dial. Maced. etc., p. 173f; 
Lob. ad Phryn., p. 339f; Schäfer ad Lamb. Bos, p. 368; (cf. 
Buttmann, 62 (55); 
Winer's Grammar, 24, 46)): 1 aorist 
ἐκάμμυσα; 
to shut the eyes, close the eyes: often with 
τούς ὀφθαλμούς added; so 
Matthew 13:15 and 
Acts 28:27 (from the 
Sept. Isaiah 6:10, for 
הָשַׁע , i. e. to besmear), in both passages the phrase designates the inflexible pertinacity and obstinacy of the Jews in their opposition to the gospel. (
Isaiah 29:10; 
Lamentations 3:43; 
καμμύειν τό τῆς ψυχῆς ὄμμα, 
Philo de somn. i. § 26.)